release: cut v2.0.0 — write support complete

Version bumped to 2.0.0 / 13. No code changes beyond the version — 2.0.0 closes out Milestone 2 (write support, v1.1 through v2.0): the final slice is the save-conflict dialog (external change → overwrite/discard, external delete → informational close), plus the store refresh: descriptions and README describe write support and reminders, and fastlane screenshots (DE+EN, six each) ship for F-Droid. CHANGELOG [2.0.0] carries the details. Quick-add was cut from scope (the prefilled form covers it); calendar switching while editing moved to the v3 backlog. Both documented in the roadmap. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
feat(edit): conflict dialog on save + store metadata refresh (v2.0)
2026-06-11 22:15:50 +02:00 · 2026-06-11 22:14:27 +02:00 · 2026-06-11 21:24:10 +02:00 · 2026-06-11 21:23:34 +02:00
47 changed files with 1490 additions and 196 deletions
--- a/.planning/ROADMAP.md
+++ b/.planning/ROADMAP.md
@@ -53,7 +53,7 @@ after v0.6 (full event read) plus the onboarding-screen polish pass.
 - ~~Redesign the initial grant-access (permission) screen~~ — **done**
  (Material 3 Expressive onboarding, shipped in v0.6.0 / v1.0.0)

-## v2.0 — Write Support (in progress)
+## v2.0 — Write Support (complete, shipped 2026-06-11)

 Delivered in four releasable slices (plan:
 `docs/superpowers/plans/2026-06-11-03-write-support.md`). The V1 spec is a
@@ -65,8 +65,22 @@ guide here, not a contract — scope per slice is decided as we go.
 | v1.2 | Create event — form, FAB, last-used-calendar preselect | complete (shipped 2026-06-11) |
 | v1.2.1 | Form polish after on-device review — card design system, optional fields + settings defaults, OptionCard dialogs, expressive motion | complete (shipped 2026-06-11) |
 | v1.3 | Edit event — shared form, scoped recurring writes (this / following / all), recurrence picker | complete (shipped 2026-06-11) |
-| v1.4 | Reminder notifications — see below | planned |
-| v2.0 | Quick-add, occurrence edit, conflict dialog, polish, release | planned |
+| v1.4 | Reminder notifications — see below | complete (shipped 2026-06-11) |
+| v2.0 | Conflict dialog, polish pass (store copy refresh, F-Droid screenshots), release | complete (shipped 2026-06-11) |
+
+v2.0 scope was re-cut on 2026-06-11, after v1.4:
+- **Occurrence edit** already shipped early, in v1.3.
+- **Quick-add** is **cut from scope**: the full form already opens prefilled
+  (visible day, last-used calendar, optional fields hidden), so the sheet
+  would only save one screen transition while adding a second create-surface
+  to maintain. Revisit only if real-world feedback says creation feels heavy.
+- **Calendar switching while editing** moves to the v3 backlog (sync-adapter
+  minefield: `CALENDAR_ID` is sync-adapter-owned, AOSP locks the field; an
+  honest implementation is copy+delete like Google Calendar, with sync-identity
+  and attendee side effects).
+- **Conflict dialog** stays (plan 03, decision 5): on save, compare against
+  the row as it was when the form loaded; on external change, ask
+  overwrite / discard. Closes the silent-clobber gap on synced calendars.

 ## v1.4 — Reminder Notifications

@@ -99,5 +113,7 @@ Deliberately deferred (add only if needed):
 - Full-text search
 - Tablet / foldable layouts
 - Optional: ICS file import (drag-and-drop)
+- Optional: move event to another calendar (copy+delete model with a
+  consequences warning — deferred from v2.0, see above)

 Order is indicative — community feedback after V1 may re-prioritize.
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,45 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 ## [Unreleased]

+## [2.0.0] — 2026-06-11
+
+### Added
+- Conflict handling when saving an edit: if the event changed elsewhere
+  (sync, another device) while the form was open, saving now asks whether
+  to keep or discard your changes instead of silently overwriting the
+  edited fields — and tells you when the event was deleted in the meantime.
+  "Keep" still writes only the fields you touched; external changes to
+  untouched fields survive either way
+- F-Droid store screenshots (German + English), captured with demo data
+
+### Changed
+- F-Droid description and README no longer claim the app is read-only —
+  they now describe write support and reminder delivery
+
+### Fixed
+- `versionName`/`versionCode` bumped to 2.0.0 / 13 — closing out the
+  write-support milestone (v1.1 through v2.0)
+
+## [1.4.0] — 2026-06-11
+
+### Added
+- Reminder notifications (v1.4): Calendula now delivers event reminders as
+  notifications itself — the system schedules them but posts nothing, so a
+  calendar app must (essential when Calendula is the only one installed).
+  Due reminders appear on a dedicated "Event reminders" channel; tapping one
+  opens the event's detail screen. Email reminders are never posted (the
+  provider only schedules alert-type reminders)
+- A one-time onboarding step after the calendar grant introduces reminders,
+  requests the notification permission (Android 13+), and warns that a second
+  calendar app with notifications on will duplicate them. "Not now" leaves
+  the feature off
+- Settings gained a "Notifications" section mirroring the choice: an event-
+  reminders toggle (default on) with the duplicate-reminders hint; turning it
+  on re-requests the notification permission when missing
+
+### Fixed
+- `versionName`/`versionCode` bumped to 1.4.0 / 12
+
 ## [1.3.0] — 2026-06-11

 ### Added
--- a/README.md
+++ b/README.md
@@ -8,10 +8,14 @@ word "calendar". Calendula reads from Android's built-in `CalendarContract`,
 so any calendar source synced to your device (CalDAV via DAVx5, Google,
 local, WebCal subscriptions, ...) is shown.

-## Features (V1)
+## Features

 - Month, Week, and Day views
- Read-only event details (write support comes in V2)
+- Full event details — attendees, reminders, recurrence, availability, and more
+- Create, edit, and delete events — recurring events with scoped writes
+  (only this event / this and all following / whole series) and a simple
+  recurrence picker
+- Reminder notifications, delivered by Calendula itself (tap opens the event)
 - Multi-calendar visibility toggle
 - Material You Dynamic Color (Android 12+)
 - Light/Dark theme follows system
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -23,8 +23,8 @@ android {
        applicationId = "de.jeanlucmakiola.calendula"
        minSdk = 29
        targetSdk = 36
-        versionCode = 11
-        versionName = "1.3.0"
+        versionCode = 13
+        versionName = "2.0.0"

        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
    }
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -4,6 +4,7 @@

    <uses-permission android:name="android.permission.READ_CALENDAR" />
    <uses-permission android:name="android.permission.WRITE_CALENDAR" />
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />

    <application
        android:name=".CalendulaApp"
@@ -19,6 +20,7 @@
        <activity
            android:name=".MainActivity"
            android:exported="true"
+            android:launchMode="singleTop"
            android:windowSoftInputMode="adjustResize">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
@@ -26,6 +28,20 @@
            </intent-filter>
        </activity>

+        <!-- The provider broadcasts EVENT_REMINDER at reminder time but posts
+             no notification itself — a calendar app must (v1.4, Etar model).
+             Exported: the broadcast arrives from the provider's process. -->
+        <receiver
+            android:name=".data.reminders.EventReminderReceiver"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.EVENT_REMINDER" />
+                <data
+                    android:host="com.android.calendar"
+                    android:scheme="content" />
+            </intent-filter>
+        </receiver>
+
        <!-- Persists the per-app language (M4) on API < 33, where the platform
             per-app-languages API is unavailable. On 33+ this is a no-op. -->
        <service
--- a/app/src/main/java/de/jeanlucmakiola/calendula/MainActivity.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/MainActivity.kt
@@ -1,5 +1,7 @@
 package de.jeanlucmakiola.calendula

+import android.content.Context
+import android.content.Intent
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
@@ -7,7 +9,10 @@ import androidx.activity.enableEdgeToEdge
 import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
+import androidx.core.net.toUri
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import dagger.hilt.android.AndroidEntryPoint
@@ -18,9 +23,16 @@ import de.jeanlucmakiola.calendula.ui.theme.CalendulaTheme

@AndroidEntryPoint
 class MainActivity : ComponentActivity() {
+
+    // The occurrence a reminder notification was tapped for (eventId, begin,
+    // end — the detail screen's key shape). singleTop + onNewIntent route a
+    // tap into the running activity; CalendarHost consumes and clears it.
+    private var requestedDetailKey by mutableStateOf<LongArray?>(null)
+
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
+        requestedDetailKey = intent.detailKeyOrNull()
        setContent {
            // One activity-scoped SettingsViewModel drives both the theme here
            // and the Settings screen, so a theme change applies app-wide at once.
@@ -35,8 +47,51 @@ class MainActivity : ComponentActivity() {
                darkTheme = darkTheme,
                dynamicColor = settings.dynamicColor,
            ) {
-                RootScreen(modifier = Modifier.fillMaxSize())
+                RootScreen(
+                    modifier = Modifier.fillMaxSize(),
+                    requestedDetailKey = requestedDetailKey,
+                    onDetailKeyConsumed = { requestedDetailKey = null },
+                )
            }
        }
    }
+
+    override fun onNewIntent(intent: Intent) {
+        super.onNewIntent(intent)
+        intent.detailKeyOrNull()?.let { requestedDetailKey = it }
+    }
+
+    private fun Intent.detailKeyOrNull(): LongArray? {
+        val eventId = getLongExtra(EXTRA_EVENT_ID, -1L)
+        if (eventId == -1L) return null
+        return longArrayOf(
+            eventId,
+            getLongExtra(EXTRA_BEGIN_MILLIS, 0L),
+            getLongExtra(EXTRA_END_MILLIS, 0L),
+        )
+    }
+
+    companion object {
+        private const val EXTRA_EVENT_ID = "de.jeanlucmakiola.calendula.extra.EVENT_ID"
+        private const val EXTRA_BEGIN_MILLIS = "de.jeanlucmakiola.calendula.extra.BEGIN"
+        private const val EXTRA_END_MILLIS = "de.jeanlucmakiola.calendula.extra.END"
+
+        /**
+         * Intent opening the detail screen of one occurrence (reminder
+         * notifications). The synthetic data URI keys the intent so
+         * PendingIntents for different occurrences never collapse into one.
+         */
+        fun eventDetailIntent(
+            context: Context,
+            eventId: Long,
+            beginMillis: Long,
+            endMillis: Long,
+        ): Intent = Intent(context, MainActivity::class.java).apply {
+            data = "calendula://event/$eventId/$beginMillis".toUri()
+            putExtra(EXTRA_EVENT_ID, eventId)
+            putExtra(EXTRA_BEGIN_MILLIS, beginMillis)
+            putExtra(EXTRA_END_MILLIS, endMillis)
+            addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+        }
+    }
 }
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/di/DataModule.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/di/DataModule.kt
@@ -14,6 +14,8 @@ import de.jeanlucmakiola.calendula.data.calendar.AndroidCalendarDataSource
 import de.jeanlucmakiola.calendula.data.calendar.CalendarDataSource
 import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
 import de.jeanlucmakiola.calendula.data.calendar.CalendarRepositoryImpl
+import de.jeanlucmakiola.calendula.data.reminders.AndroidReminderAlertStore
+import de.jeanlucmakiola.calendula.data.reminders.ReminderAlertStore
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.Dispatchers
 import javax.inject.Singleton
@@ -37,6 +39,12 @@ abstract class DataBindModule {
    abstract fun bindCalendarRepository(
        impl: CalendarRepositoryImpl,
    ): CalendarRepository
+
+    @Binds
+    @Singleton
+    abstract fun bindReminderAlertStore(
+        impl: AndroidReminderAlertStore,
+    ): ReminderAlertStore
 }

@Module
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefs.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefs.kt
@@ -86,6 +86,31 @@ class SettingsPrefs @Inject constructor(
        }
    }

+    /**
+     * Whether Calendula posts reminder notifications (v1.4). Defaults to ON —
+     * for users whose only calendar app this is, reminders are essential; the
+     * onboarding step and Settings warn about duplicates from a second app.
+     */
+    val remindersEnabled: Flow<Boolean> = store.data.map { prefs ->
+        prefs[REMINDERS_ENABLED_KEY] ?: true
+    }
+
+    suspend fun setRemindersEnabled(enabled: Boolean) {
+        store.edit { it[REMINDERS_ENABLED_KEY] = enabled }
+    }
+
+    /**
+     * Whether the one-time reminder onboarding step (after the calendar
+     * grant) has been shown — also true for users who tapped "not now".
+     */
+    val reminderOnboardingDone: Flow<Boolean> = store.data.map { prefs ->
+        prefs[REMINDER_ONBOARDING_KEY] ?: false
+    }
+
+    suspend fun setReminderOnboardingDone() {
+        store.edit { it[REMINDER_ONBOARDING_KEY] = true }
+    }
+
    private fun parseFormFields(stored: String?): Set<EventFormField> = when (stored) {
        null -> DEFAULT_FORM_FIELDS
        else -> stored.split(',')
@@ -98,6 +123,8 @@ class SettingsPrefs @Inject constructor(
        internal val DYNAMIC_COLOR_KEY = booleanPreferencesKey("dynamic_color")
        internal val WEEK_START_KEY = stringPreferencesKey("week_start")
        internal val FORM_FIELDS_KEY = stringPreferencesKey("event_form_default_fields")
+        internal val REMINDERS_ENABLED_KEY = booleanPreferencesKey("reminders_enabled")
+        internal val REMINDER_ONBOARDING_KEY = booleanPreferencesKey("reminder_onboarding_done")
        internal val DEFAULT_FORM_FIELDS =
            setOf(EventFormField.Location, EventFormField.Description)
    }
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/EventReminderReceiver.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/EventReminderReceiver.kt
@@ -0,0 +1,57 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import android.Manifest
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.provider.CalendarContract
+import androidx.core.content.ContextCompat
+import dagger.hilt.android.AndroidEntryPoint
+import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.launch
+import javax.inject.Inject
+
+/**
+ * Becomes the app that turns the calendar provider's reminder alarms into
+ * visible notifications (the Etar model — the provider broadcasts
+ * `EVENT_REMINDER` at reminder time but posts nothing itself).
+ *
+ * The broadcast's data URI only carries the alarm time, so it is ignored:
+ * we query every still-scheduled, due `CalendarAlerts` row ourselves, post
+ * them, and mark them fired. Posting happens before marking — a crash in
+ * between re-posts silently (same tag) rather than losing the reminder.
+ */
+@AndroidEntryPoint
+class EventReminderReceiver : BroadcastReceiver() {
+
+    @Inject lateinit var alertStore: ReminderAlertStore
+    @Inject lateinit var notifier: ReminderNotifier
+    @Inject lateinit var settingsPrefs: SettingsPrefs
+
+    override fun onReceive(context: Context, intent: Intent) {
+        if (intent.action != CalendarContract.ACTION_EVENT_REMINDER) return
+        val readGranted = ContextCompat.checkSelfPermission(
+            context, Manifest.permission.READ_CALENDAR,
+        ) == PackageManager.PERMISSION_GRANTED
+        if (!readGranted || !notifier.canPost()) return
+
+        val pendingResult = goAsync()
+        CoroutineScope(SupervisorJob() + Dispatchers.IO).launch {
+            try {
+                if (settingsPrefs.remindersEnabled.first()) {
+                    val now = System.currentTimeMillis()
+                    val due = alertStore.dueAlerts(now)
+                    due.forEach(notifier::post)
+                    alertStore.markFired(due.map { it.alertId }, now)
+                }
+            } finally {
+                pendingResult.finish()
+            }
+        }
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderAlertStore.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderAlertStore.kt
@@ -0,0 +1,112 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import android.content.ContentValues
+import android.content.Context
+import android.provider.CalendarContract
+import android.util.Log
+import dagger.hilt.android.qualifiers.ApplicationContext
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * One due row of the provider's `CalendarAlerts` table (a join with Events).
+ * Stays in the data layer: alerts feed the notification path only and never
+ * reach a screen, so there is no domain model for them.
+ */
+data class ReminderAlert(
+    val alertId: Long,
+    val eventId: Long,
+    val beginMillis: Long,
+    val endMillis: Long,
+    /** Raw event title; may be blank — the notifier substitutes "(no title)". */
+    val title: String,
+    val location: String?,
+    val isAllDay: Boolean,
+)
+
+/**
+ * Seam over the `CalendarAlerts` table so the receiver logic can be exercised
+ * without a ContentResolver. The provider creates these rows itself — only
+ * for `METHOD_ALERT` reminders (verified in AOSP `CalendarAlarmManager`), so
+ * email reminders never show up here.
+ */
+interface ReminderAlertStore {
+
+    /** Alerts that are due (`ALARM_TIME` has passed) and still unhandled. */
+    fun dueAlerts(nowMillis: Long): List<ReminderAlert>
+
+    /**
+     * Mark the given alerts handled (`STATE_FIRED`) so a later broadcast does
+     * not surface them again. Best effort: this write needs `WRITE_CALENDAR`,
+     * which the user may have declined — then re-broadcasts silently replace
+     * the already-posted notifications instead (same tag, alert-once).
+     */
+    fun markFired(alertIds: List<Long>, nowMillis: Long)
+}
+
+@Singleton
+class AndroidReminderAlertStore @Inject constructor(
+    @ApplicationContext private val context: Context,
+) : ReminderAlertStore {
+
+    override fun dueAlerts(nowMillis: Long): List<ReminderAlert> = context.contentResolver.query(
+        CalendarContract.CalendarAlerts.CONTENT_URI,
+        PROJECTION,
+        CalendarContract.CalendarAlerts.STATE + " = ? AND " +
+            CalendarContract.CalendarAlerts.ALARM_TIME + " <= ?",
+        arrayOf(
+            CalendarContract.CalendarAlerts.STATE_SCHEDULED.toString(),
+            nowMillis.toString(),
+        ),
+        CalendarContract.CalendarAlerts.BEGIN + " ASC",
+    )?.use { c ->
+        buildList {
+            while (c.moveToNext()) {
+                add(
+                    ReminderAlert(
+                        alertId = c.getLong(0),
+                        eventId = c.getLong(1),
+                        beginMillis = c.getLong(2),
+                        endMillis = c.getLong(3),
+                        title = c.getString(4).orEmpty(),
+                        location = c.getString(5)?.takeIf { it.isNotBlank() },
+                        isAllDay = c.getInt(6) == 1,
+                    ),
+                )
+            }
+        }
+    } ?: emptyList()
+
+    override fun markFired(alertIds: List<Long>, nowMillis: Long) {
+        if (alertIds.isEmpty()) return
+        val values = ContentValues().apply {
+            put(CalendarContract.CalendarAlerts.STATE, CalendarContract.CalendarAlerts.STATE_FIRED)
+            put(CalendarContract.CalendarAlerts.RECEIVED_TIME, nowMillis)
+            put(CalendarContract.CalendarAlerts.NOTIFY_TIME, nowMillis)
+        }
+        try {
+            context.contentResolver.update(
+                CalendarContract.CalendarAlerts.CONTENT_URI,
+                values,
+                CalendarContract.CalendarAlerts._ID +
+                    " IN (" + alertIds.joinToString(",") + ")",
+                null,
+            )
+        } catch (e: SecurityException) {
+            Log.w(TAG, "Cannot mark alerts fired without WRITE_CALENDAR", e)
+        }
+    }
+
+    private companion object {
+        const val TAG = "ReminderAlertStore"
+        val PROJECTION = arrayOf(
+            CalendarContract.CalendarAlerts._ID,
+            CalendarContract.CalendarAlerts.EVENT_ID,
+            CalendarContract.CalendarAlerts.BEGIN,
+            CalendarContract.CalendarAlerts.END,
+            CalendarContract.CalendarAlerts.TITLE,
+            CalendarContract.CalendarAlerts.EVENT_LOCATION,
+            CalendarContract.CalendarAlerts.ALL_DAY,
+        )
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderNotifier.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderNotifier.kt
@@ -0,0 +1,101 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import android.Manifest
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.content.Context
+import android.content.pm.PackageManager
+import android.os.Build
+import android.util.Log
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import androidx.core.content.ContextCompat
+import dagger.hilt.android.qualifiers.ApplicationContext
+import de.jeanlucmakiola.calendula.MainActivity
+import de.jeanlucmakiola.calendula.R
+import java.time.ZoneId
+import java.util.Locale
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * Posts one notification per due reminder alert on a dedicated channel.
+ * Tapping opens the event's detail screen; the tag is the alert id, so a
+ * re-broadcast of an alert we couldn't mark fired replaces its notification
+ * silently ([NotificationCompat.Builder.setOnlyAlertOnce]) instead of
+ * duplicating it.
+ */
+@Singleton
+class ReminderNotifier @Inject constructor(
+    @ApplicationContext private val context: Context,
+) {
+
+    /** False when the user declined `POST_NOTIFICATIONS` or muted the app. */
+    fun canPost(): Boolean {
+        val granted = Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU ||
+            ContextCompat.checkSelfPermission(context, Manifest.permission.POST_NOTIFICATIONS) ==
+            PackageManager.PERMISSION_GRANTED
+        return granted && NotificationManagerCompat.from(context).areNotificationsEnabled()
+    }
+
+    fun post(alert: ReminderAlert) {
+        ensureChannel()
+        val title = alert.title.ifBlank { context.getString(R.string.event_untitled) }
+        val time = reminderTimeText(
+            beginMillis = alert.beginMillis,
+            endMillis = alert.endMillis,
+            isAllDay = alert.isAllDay,
+            zone = ZoneId.systemDefault(),
+            locale = Locale.getDefault(),
+        )
+        val text = listOfNotNull(time, alert.location).joinToString(" · ")
+        val notification = NotificationCompat.Builder(context, CHANNEL_ID)
+            .setSmallIcon(R.drawable.ic_notification)
+            .setContentTitle(title)
+            .setContentText(text)
+            .setWhen(alert.beginMillis)
+            .setShowWhen(false)
+            .setCategory(NotificationCompat.CATEGORY_EVENT)
+            .setPriority(NotificationCompat.PRIORITY_HIGH)
+            .setAutoCancel(true)
+            .setOnlyAlertOnce(true)
+            .setContentIntent(detailIntent(alert))
+            .build()
+        try {
+            NotificationManagerCompat.from(context)
+                .notify(alert.alertId.toString(), NOTIFICATION_ID, notification)
+        } catch (e: SecurityException) {
+            // POST_NOTIFICATIONS was revoked between canPost() and here.
+            Log.w(TAG, "Could not post reminder for event ${alert.eventId}", e)
+        }
+    }
+
+    private fun detailIntent(alert: ReminderAlert): PendingIntent = PendingIntent.getActivity(
+        context,
+        /* requestCode = */ alert.alertId.toInt(),
+        MainActivity.eventDetailIntent(context, alert.eventId, alert.beginMillis, alert.endMillis),
+        PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
+    )
+
+    /** Channel creation is idempotent; re-running refreshes the localized name. */
+    private fun ensureChannel() {
+        val channel = NotificationChannel(
+            CHANNEL_ID,
+            context.getString(R.string.reminder_channel_name),
+            NotificationManager.IMPORTANCE_HIGH,
+        ).apply {
+            description = context.getString(R.string.reminder_channel_description)
+        }
+        NotificationManagerCompat.from(context).createNotificationChannel(channel)
+    }
+
+    private companion object {
+        const val TAG = "ReminderNotifier"
+        const val CHANNEL_ID = "reminders"
+
+        // One id, distinct tags: the tag (alert id) already keys the
+        // notification, so a fixed id keeps cancellation/replacement simple.
+        const val NOTIFICATION_ID = 1
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderTimeText.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/reminders/ReminderTimeText.kt
@@ -0,0 +1,56 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import java.time.Instant
+import java.time.ZoneId
+import java.time.ZoneOffset
+import java.time.format.DateTimeFormatter
+import java.time.format.FormatStyle
+import java.util.Locale
+
+/**
+ * The one line of time context in a reminder notification. Pure so it can be
+ * JVM-tested:
+ *
+ * - timed, same day:      "09:30 – 10:00"
+ * - timed, crossing days: "11 Jun, 23:30 – 12 Jun, 00:30" (medium date + short time)
+ * - all-day, one day:     "11 Jun 2026"
+ * - all-day, multi-day:   "11 Jun 2026 – 12 Jun 2026"
+ *
+ * All-day instances store UTC midnights with an exclusive end, so they are
+ * read in UTC and the end day is the last *covered* day.
+ */
+fun reminderTimeText(
+    beginMillis: Long,
+    endMillis: Long,
+    isAllDay: Boolean,
+    zone: ZoneId,
+    locale: Locale,
+): String {
+    if (isAllDay) {
+        val dateFormat = DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM).withLocale(locale)
+        // (atZone().toLocalDate() instead of LocalDate.ofInstant — API 34+)
+        val firstDay = Instant.ofEpochMilli(beginMillis).atZone(ZoneOffset.UTC).toLocalDate()
+        val lastDay = Instant.ofEpochMilli(endMillis).atZone(ZoneOffset.UTC).toLocalDate()
+            .minusDays(1)
+            .coerceAtLeast(firstDay)
+        return if (lastDay == firstDay) {
+            dateFormat.format(firstDay)
+        } else {
+            dateFormat.format(firstDay) + RANGE + dateFormat.format(lastDay)
+        }
+    }
+
+    val timeFormat = DateTimeFormatter.ofLocalizedTime(FormatStyle.SHORT).withLocale(locale)
+    val begin = Instant.ofEpochMilli(beginMillis).atZone(zone)
+    val end = Instant.ofEpochMilli(endMillis).atZone(zone)
+    return if (begin.toLocalDate() == end.toLocalDate()) {
+        timeFormat.format(begin) + RANGE + timeFormat.format(end)
+    } else {
+        val dateTimeFormat = DateTimeFormatter
+            .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT)
+            .withLocale(locale)
+        dateTimeFormat.format(begin) + RANGE + dateTimeFormat.format(end)
+    }
+}
+
+private const val RANGE = " – "
--- a/app/src/main/java/de/jeanlucmakiola/calendula/domain/EventForm.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/domain/EventForm.kt
@@ -94,6 +94,30 @@ fun EventDetail.toEditForm(beginMillis: Long, endMillis: Long, zone: TimeZone):
    )
 }

+/**
+ * What the edit form saw when it loaded — compared against a fresh read at
+ * save time to detect external changes (sync, another device) that landed
+ * while the form was open. The raw row times ride along because
+ * [toEditForm] derives the form's times from the *tapped occurrence*, so
+ * re-deriving with the same occurrence would mask an externally moved
+ * event. Not covered (the form can't write them, and the dirty-checked
+ * write can't clobber them): attendees, status, the user's own response,
+ * reminder methods, and a recurring event's duration.
+ */
+data class EditSnapshot(
+    val form: EventForm,
+    /** The raw Events-row times (for recurring events: the series anchor). */
+    val rowStart: Instant,
+    val rowEnd: Instant,
+)
+
+fun EventDetail.toEditSnapshot(beginMillis: Long, endMillis: Long, zone: TimeZone): EditSnapshot =
+    EditSnapshot(
+        form = toEditForm(beginMillis, endMillis, zone),
+        rowStart = instance.start,
+        rowEnd = instance.end,
+    )
+
 /**
 * The optional sections that hold a value in [form] — when editing, these
 * must be visible regardless of the user's default-fields setting, or the
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/CalendarHost.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/CalendarHost.kt
@@ -8,6 +8,7 @@ import androidx.compose.animation.slideOutHorizontally
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
@@ -29,9 +30,18 @@ import kotlinx.datetime.LocalDate
 * Holds the active top-level view (spec M1) and swaps between the calendar
 * screens. Each screen owns its own ViewModel and date anchor; the view-switcher
 * pill in their top bars writes back here via [onSelectView].
+ *
+ * [requestedDetailKey] is an externally requested occurrence (a tapped
+ * reminder notification routed through MainActivity): it opens the detail
+ * overlay exactly like an event tap and is cleared via [onDetailKeyConsumed]
+ * so a later recomposition can't re-open it.
 */
@Composable
-fun CalendarHost(modifier: Modifier = Modifier) {
+fun CalendarHost(
+    modifier: Modifier = Modifier,
+    requestedDetailKey: LongArray? = null,
+    onDetailKeyConsumed: () -> Unit = {},
+) {
    var view by rememberSaveable { mutableStateOf(CalendarView.Week) }
    val onSelectView: (CalendarView) -> Unit = { view = it }

@@ -61,6 +71,15 @@ fun CalendarHost(modifier: Modifier = Modifier) {
        detailKey = key
    }

+    // A tapped reminder notification asks for a specific occurrence.
+    LaunchedEffect(requestedDetailKey) {
+        if (requestedDetailKey != null) {
+            heldKey = requestedDetailKey
+            detailKey = requestedDetailKey
+            onDetailKeyConsumed()
+        }
+    }
+
    // Settings (M4) is hoisted here so it overlays whichever calendar view is
    // active and survives view switches. (The calendar filter now lives inline
    // in the navigation drawer, so no overlay state is needed for it.)
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/RootScreen.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/RootScreen.kt
@@ -10,14 +10,22 @@ import androidx.compose.runtime.setValue
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
+import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.LocalLifecycleOwner
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.core.content.ContextCompat
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleEventObserver
 import de.jeanlucmakiola.calendula.ui.permission.PermissionScreen
+import de.jeanlucmakiola.calendula.ui.permission.ReminderOnboardingScreen
+import de.jeanlucmakiola.calendula.ui.permission.ReminderOnboardingViewModel

@Composable
-fun RootScreen(modifier: Modifier = Modifier) {
+fun RootScreen(
+    modifier: Modifier = Modifier,
+    requestedDetailKey: LongArray? = null,
+    onDetailKeyConsumed: () -> Unit = {},
+) {
    val context = LocalContext.current
    var hasPermission by remember {
        mutableStateOf(
@@ -40,7 +48,23 @@ fun RootScreen(modifier: Modifier = Modifier) {
    }

    if (hasPermission) {
-        CalendarHost(modifier = modifier)
+        // Second onboarding gate (v1.4, one-time): reminder notifications.
+        // Null until DataStore's first emission — render nothing for that
+        // frame instead of flashing the wrong screen.
+        val reminderOnboarding: ReminderOnboardingViewModel = hiltViewModel()
+        val onboardingDone by reminderOnboarding.onboardingDone.collectAsStateWithLifecycle()
+        when (onboardingDone) {
+            true -> CalendarHost(
+                modifier = modifier,
+                requestedDetailKey = requestedDetailKey,
+                onDetailKeyConsumed = onDetailKeyConsumed,
+            )
+            false -> ReminderOnboardingScreen(
+                onFinished = reminderOnboarding::finish,
+                modifier = modifier,
+            )
+            null -> {}
+        }
    } else {
        PermissionScreen(
            onGranted = { hasPermission = true },
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditScreen.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditScreen.kt
@@ -217,7 +217,8 @@ fun EventEditScreen(
                viewModel.consumeSaveResult()
                snackbarHostState.showSnackbar(writeDeniedMessage)
            }
-            SaveUiState.Idle, SaveUiState.AwaitingScope, SaveUiState.Saving, null -> Unit
+            // AwaitingScope/AwaitingConflict/Gone render as dialogs below.
+            else -> Unit
        }
    }

@@ -269,6 +270,68 @@ fun EventEditScreen(
            onDismiss = viewModel::consumeSaveResult,
        )
    }
+
+    // The event changed externally (sync) while the form was open (v2.0).
+    if (state?.saveState is SaveUiState.AwaitingConflict) {
+        SaveConflictDialog(
+            onOverwrite = viewModel::saveOverwriting,
+            onDiscard = close,
+            onDismiss = viewModel::consumeSaveResult,
+        )
+    }
+
+    // ...or was deleted underneath us — nothing left to save onto. Closing
+    // through [onSaved] also pops the detail screen, whose occurrence is gone.
+    if (state?.saveState == SaveUiState.Gone) {
+        AlertDialog(
+            onDismissRequest = {},
+            title = { Text(stringResource(R.string.event_edit_gone_title)) },
+            text = { Text(stringResource(R.string.event_edit_gone_body)) },
+            confirmButton = {
+                TextButton(onClick = {
+                    viewModel.reset()
+                    onSaved()
+                }) { Text(stringResource(R.string.dialog_ok)) }
+            },
+        )
+    }
+}
+
+/**
+ * Overwrite-or-discard choice when the event changed underneath an open
+ * form (no locking; detected by re-reading at save time). "Overwrite" still
+ * only writes the fields the user edited — external changes to untouched
+ * fields survive either way. Cancelling returns to the form.
+ */
+@Composable
+private fun SaveConflictDialog(
+    onOverwrite: () -> Unit,
+    onDiscard: () -> Unit,
+    onDismiss: () -> Unit,
+) {
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringResource(R.string.event_edit_conflict_title)) },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                Text(stringResource(R.string.event_edit_conflict_body))
+                Spacer(Modifier.height(4.dp))
+                OptionCard(
+                    label = stringResource(R.string.event_edit_conflict_overwrite),
+                    supportingText = stringResource(R.string.event_edit_conflict_overwrite_hint),
+                    onClick = onOverwrite,
+                )
+                OptionCard(
+                    label = stringResource(R.string.event_edit_conflict_discard),
+                    supportingText = stringResource(R.string.event_edit_conflict_discard_hint),
+                    onClick = onDiscard,
+                )
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = onDismiss) { Text(stringResource(R.string.dialog_cancel)) }
+        },
+    )
 }

 /**
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditUiState.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditUiState.kt
@@ -4,6 +4,7 @@ import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventForm
 import de.jeanlucmakiola.calendula.domain.EventFormField
 import de.jeanlucmakiola.calendula.domain.EventFormProblem
+import de.jeanlucmakiola.calendula.domain.RecurringWriteScope

 /**
 * UI state for the event form (v1.2: create; v1.3 reuses it for edit). Null
@@ -39,6 +40,14 @@ sealed interface SaveUiState {
    data object Idle : SaveUiState
    /** A dirty recurring event waits for the user to pick the write scope. */
    data object AwaitingScope : SaveUiState
+    /**
+     * The event changed externally (sync) while the form was open; the save
+     * is parked with its chosen [scope] until the user picks overwrite,
+     * discard, or cancel.
+     */
+    data class AwaitingConflict(val scope: RecurringWriteScope) : SaveUiState
+    /** The event was deleted externally while the form was open. */
+    data object Gone : SaveUiState
    data object Saving : SaveUiState
    data object Saved : SaveUiState
    /** WRITE_CALENDAR was revoked between the tap and the provider call. */
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditViewModel.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditViewModel.kt
@@ -4,18 +4,20 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
+import de.jeanlucmakiola.calendula.data.calendar.NoSuchEventException
 import de.jeanlucmakiola.calendula.data.di.IoDispatcher
 import de.jeanlucmakiola.calendula.data.prefs.CalendarPrefs
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 import de.jeanlucmakiola.calendula.domain.AccessLevel
 import de.jeanlucmakiola.calendula.domain.Availability
 import de.jeanlucmakiola.calendula.domain.CalendarSource
+import de.jeanlucmakiola.calendula.domain.EditSnapshot
 import de.jeanlucmakiola.calendula.domain.EventForm
 import de.jeanlucmakiola.calendula.domain.EventFormField
 import de.jeanlucmakiola.calendula.domain.RecurringWriteScope
 import de.jeanlucmakiola.calendula.domain.populatedFields
 import de.jeanlucmakiola.calendula.domain.problems
-import de.jeanlucmakiola.calendula.domain.toEditForm
+import de.jeanlucmakiola.calendula.domain.toEditSnapshot
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -68,15 +70,21 @@ class EventEditViewModel @Inject constructor(
    val loadFailed: StateFlow<Boolean> = _loadFailed.asStateFlow()

    /**
-     * The event being edited plus the form exactly as it was prefilled.
+     * The event being edited plus everything the form saw at load time.
     * For recurring events the write scope is chosen at save time; the
-     * tapped occurrence's [beginMillis] anchors occurrence-level writes.
+     * tapped occurrence's [beginMillis]/[endMillis] anchor occurrence-level
+     * writes and the conflict re-read. [zone] is pinned at load so a device
+     * timezone change mid-edit can't fake a conflict.
     */
    private data class EditTarget(
        val eventId: Long,
-        val original: EventForm,
+        val snapshot: EditSnapshot,
        val beginMillis: Long,
-    )
+        val endMillis: Long,
+        val zone: TimeZone,
+    ) {
+        val original: EventForm get() = snapshot.form
+    }

    private data class LocalInputs(
        val form: EventForm?,
@@ -167,11 +175,12 @@ class EventEditViewModel @Inject constructor(
                _loadFailed.value = true
                return@launch
            }
-            val original = detail.toEditForm(beginMillis, endMillis, TimeZone.currentSystemDefault())
-            _editTarget.value = EditTarget(eventId, original, beginMillis)
+            val zone = TimeZone.currentSystemDefault()
+            val snapshot = detail.toEditSnapshot(beginMillis, endMillis, zone)
+            _editTarget.value = EditTarget(eventId, snapshot, beginMillis, endMillis, zone)
            // Sections holding data must show even when not in the defaults.
-            _revealed.value = original.populatedFields()
-            _form.value = original
+            _revealed.value = snapshot.form.populatedFields()
+            _form.value = snapshot.form
        }
    }

@@ -249,10 +258,43 @@ class EventEditViewModel @Inject constructor(
        performSave(current.form, scope)
    }

-    private fun performSave(form: EventForm, scope: RecurringWriteScope) {
+    /** Finish a save parked in [SaveUiState.AwaitingConflict], overwriting. */
+    fun saveOverwriting() {
+        val current = state.value ?: return
+        val parked = current.saveState as? SaveUiState.AwaitingConflict ?: return
+        performSave(current.form, parked.scope, ignoreConflict = true)
+    }
+
+    private fun performSave(
+        form: EventForm,
+        scope: RecurringWriteScope,
+        ignoreConflict: Boolean = false,
+    ) {
        val target = _editTarget.value
        viewModelScope.launch {
            _saveState.value = SaveUiState.Saving
+            // No locking (plan 03, decision 5): right before writing, re-read
+            // the event and compare against what the form loaded. An external
+            // change parks the save in a conflict dialog instead of silently
+            // clobbering the edited fields.
+            if (target != null && !ignoreConflict) {
+                val fresh = try {
+                    repository.eventDetail(target.eventId)
+                        .toEditSnapshot(target.beginMillis, target.endMillis, target.zone)
+                } catch (e: CancellationException) {
+                    throw e
+                } catch (e: NoSuchEventException) {
+                    _saveState.value = SaveUiState.Gone
+                    return@launch
+                } catch (e: Exception) {
+                    // Can't verify — proceed; a real problem fails the write itself.
+                    null
+                }
+                if (fresh != null && fresh != target.snapshot) {
+                    _saveState.value = SaveUiState.AwaitingConflict(scope)
+                    return@launch
+                }
+            }
            _saveState.value = try {
                if (target == null) {
                    repository.createEvent(form)
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/OnboardingScaffold.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/OnboardingScaffold.kt
@@ -0,0 +1,163 @@
+package de.jeanlucmakiola.calendula.ui.permission
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.ColumnScope
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.navigationBarsPadding
+import androidx.compose.foundation.layout.offset
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Lock
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.res.colorResource
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.unit.dp
+import de.jeanlucmakiola.calendula.R
+
+/** MD3 8dp spacing scale shared by the onboarding screens. */
+internal object OnboardingSpace {
+    val xs = 8.dp
+    val sm = 16.dp
+    val md = 24.dp
+    val lg = 32.dp
+    val xl = 48.dp
+}
+
+/**
+ * Shared onboarding shell (calendar grant, reminder step): a scrollable,
+ * centred hero + body with the call(s) to action pinned to the bottom (clear
+ * of the navigation bar). The content slot is centred horizontally; benefit
+ * rows fill the width so their own content left-aligns.
+ */
+@Composable
+internal fun OnboardingScaffold(
+    hero: @Composable () -> Unit,
+    actions: @Composable ColumnScope.() -> Unit,
+    modifier: Modifier = Modifier,
+    body: @Composable ColumnScope.() -> Unit,
+) {
+    Scaffold(
+        modifier = modifier,
+        containerColor = MaterialTheme.colorScheme.surface,
+        bottomBar = {
+            Column(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .navigationBarsPadding()
+                    .padding(horizontal = OnboardingSpace.md, vertical = OnboardingSpace.sm),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.spacedBy(4.dp),
+                content = actions,
+            )
+        },
+    ) { innerPadding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(innerPadding)
+                .verticalScroll(rememberScrollState())
+                .padding(horizontal = OnboardingSpace.md),
+            horizontalAlignment = Alignment.CenterHorizontally,
+        ) {
+            Spacer(Modifier.height(OnboardingSpace.xl))
+            hero()
+            Spacer(Modifier.height(OnboardingSpace.lg))
+            body()
+            Spacer(Modifier.height(OnboardingSpace.md))
+        }
+    }
+}
+
+/** The app's adaptive launcher mark, reconstructed as a large branded squircle. */
+@Composable
+internal fun BrandHero(denied: Boolean) {
+    Box(contentAlignment = Alignment.Center) {
+        Box(
+            modifier = Modifier
+                .size(128.dp)
+                .clip(RoundedCornerShape(34.dp))
+                .background(colorResource(R.color.ic_launcher_background)),
+        ) {
+            Image(
+                painter = painterResource(R.drawable.ic_launcher_foreground),
+                contentDescription = stringResource(R.string.app_name),
+                modifier = Modifier.fillMaxSize(),
+            )
+        }
+        if (denied) {
+            // A small lock badge sits over the corner to signal "blocked".
+            Box(
+                modifier = Modifier
+                    .align(Alignment.BottomEnd)
+                    .offset(x = 10.dp, y = 10.dp)
+                    .size(44.dp)
+                    .clip(CircleShape)
+                    .background(MaterialTheme.colorScheme.errorContainer),
+                contentAlignment = Alignment.Center,
+            ) {
+                Icon(
+                    imageVector = Icons.Filled.Lock,
+                    contentDescription = null,
+                    tint = MaterialTheme.colorScheme.onErrorContainer,
+                    modifier = Modifier.size(24.dp),
+                )
+            }
+        }
+    }
+}
+
+/** One trust point: a tonal icon chip on the left, title + supporting text right. */
+@Composable
+internal fun BenefitRow(icon: ImageVector, title: String, body: String) {
+    Row(
+        modifier = Modifier.fillMaxWidth(),
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        Box(
+            modifier = Modifier
+                .size(44.dp)
+                .clip(CircleShape)
+                .background(MaterialTheme.colorScheme.secondaryContainer),
+            contentAlignment = Alignment.Center,
+        ) {
+            Icon(
+                imageVector = icon,
+                contentDescription = null,
+                tint = MaterialTheme.colorScheme.onSecondaryContainer,
+                modifier = Modifier.size(22.dp),
+            )
+        }
+        Spacer(Modifier.width(OnboardingSpace.sm))
+        Column(modifier = Modifier.weight(1f)) {
+            Text(text = title, style = MaterialTheme.typography.titleMedium)
+            Text(
+                text = body,
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/PermissionScreen.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/PermissionScreen.kt
@@ -6,25 +6,14 @@ import android.net.Uri
 import android.provider.Settings
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
-import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Arrangement
-import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
-import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
-import androidx.compose.foundation.layout.navigationBarsPadding
-import androidx.compose.foundation.layout.offset
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
-import androidx.compose.foundation.rememberScrollState
-import androidx.compose.foundation.shape.CircleShape
-import androidx.compose.foundation.shape.RoundedCornerShape
-import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowForward
 import androidx.compose.material.icons.filled.CalendarMonth
@@ -34,7 +23,6 @@ import androidx.compose.material3.Button
 import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
@@ -42,18 +30,13 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.draw.clip
-import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.platform.LocalContext
-import androidx.compose.ui.res.colorResource
-import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
-import androidx.compose.foundation.Image
 import de.jeanlucmakiola.calendula.R

 private val CALENDAR_PERMISSIONS = arrayOf(
@@ -61,15 +44,6 @@ private val CALENDAR_PERMISSIONS = arrayOf(
    Manifest.permission.WRITE_CALENDAR,
 )

-// MD3 8dp spacing scale, scoped to this screen.
-private object Space {
-    val xs = 8.dp
-    val sm = 16.dp
-    val md = 24.dp
-    val lg = 32.dp
-    val xl = 48.dp
-}
-
@Composable
 fun PermissionScreen(
    onGranted: () -> Unit,
@@ -118,7 +92,7 @@ private fun RationaleContent(
    onRequest: () -> Unit,
    modifier: Modifier = Modifier,
 ) {
-    PermissionScaffold(
+    OnboardingScaffold(
        modifier = modifier,
        hero = { BrandHero(denied = false) },
        actions = {
@@ -131,7 +105,7 @@ private fun RationaleContent(
                    text = stringResource(R.string.permission_request_button),
                    style = MaterialTheme.typography.titleMedium,
                )
-                Spacer(Modifier.width(Space.xs))
+                Spacer(Modifier.width(OnboardingSpace.xs))
                Icon(
                    imageVector = Icons.AutoMirrored.Filled.ArrowForward,
                    contentDescription = null,
@@ -147,7 +121,7 @@ private fun RationaleContent(
            color = MaterialTheme.colorScheme.primary,
            letterSpacing = 2.sp,
        )
-        Spacer(Modifier.height(Space.xs))
+        Spacer(Modifier.height(OnboardingSpace.xs))
        Text(
            text = stringResource(R.string.permission_rationale_title),
            style = MaterialTheme.typography.headlineMedium,
@@ -161,20 +135,20 @@ private fun RationaleContent(
            textAlign = TextAlign.Center,
        )

-        Spacer(Modifier.height(Space.xl))
+        Spacer(Modifier.height(OnboardingSpace.xl))

        BenefitRow(
            icon = Icons.Filled.Lock,
            title = stringResource(R.string.permission_benefit_private_title),
            body = stringResource(R.string.permission_benefit_private_body),
        )
-        Spacer(Modifier.height(Space.sm))
+        Spacer(Modifier.height(OnboardingSpace.sm))
        BenefitRow(
            icon = Icons.Filled.CalendarMonth,
            title = stringResource(R.string.permission_benefit_sync_title),
            body = stringResource(R.string.permission_benefit_sync_body),
        )
-        Spacer(Modifier.height(Space.sm))
+        Spacer(Modifier.height(OnboardingSpace.sm))
        BenefitRow(
            icon = Icons.Filled.VisibilityOff,
            title = stringResource(R.string.permission_benefit_privacy_title),
@@ -189,7 +163,7 @@ private fun DeniedContent(
    modifier: Modifier = Modifier,
 ) {
    val context = LocalContext.current
-    PermissionScaffold(
+    OnboardingScaffold(
        modifier = modifier,
        hero = { BrandHero(denied = true) },
        actions = {
@@ -231,122 +205,6 @@ private fun DeniedContent(
    }
 }

-/**
- * Shared onboarding shell: a scrollable, centred hero + body with the call(s) to
- * action pinned to the bottom (clear of the navigation bar). The content slot is
- * centred horizontally; benefit rows fill the width so their own content
- * left-aligns.
- */
-@Composable
-private fun PermissionScaffold(
-    hero: @Composable () -> Unit,
-    actions: @Composable ColumnScope.() -> Unit,
-    modifier: Modifier = Modifier,
-    body: @Composable ColumnScope.() -> Unit,
-) {
-    Scaffold(
-        modifier = modifier,
-        containerColor = MaterialTheme.colorScheme.surface,
-        bottomBar = {
-            Column(
-                modifier = Modifier
-                    .fillMaxWidth()
-                    .navigationBarsPadding()
-                    .padding(horizontal = Space.md, vertical = Space.sm),
-                horizontalAlignment = Alignment.CenterHorizontally,
-                verticalArrangement = Arrangement.spacedBy(4.dp),
-                content = actions,
-            )
-        },
-    ) { innerPadding ->
-        Column(
-            modifier = Modifier
-                .fillMaxSize()
-                .padding(innerPadding)
-                .verticalScroll(rememberScrollState())
-                .padding(horizontal = Space.md),
-            horizontalAlignment = Alignment.CenterHorizontally,
-        ) {
-            Spacer(Modifier.height(Space.xl))
-            hero()
-            Spacer(Modifier.height(Space.lg))
-            body()
-            Spacer(Modifier.height(Space.md))
-        }
-    }
-}
-
-/** The app's adaptive launcher mark, reconstructed as a large branded squircle. */
-@Composable
-private fun BrandHero(denied: Boolean) {
-    Box(contentAlignment = Alignment.Center) {
-        Box(
-            modifier = Modifier
-                .size(128.dp)
-                .clip(RoundedCornerShape(34.dp))
-                .background(colorResource(R.color.ic_launcher_background)),
-        ) {
-            Image(
-                painter = painterResource(R.drawable.ic_launcher_foreground),
-                contentDescription = stringResource(R.string.app_name),
-                modifier = Modifier.fillMaxSize(),
-            )
-        }
-        if (denied) {
-            // A small lock badge sits over the corner to signal "blocked".
-            Box(
-                modifier = Modifier
-                    .align(Alignment.BottomEnd)
-                    .offset(x = 10.dp, y = 10.dp)
-                    .size(44.dp)
-                    .clip(CircleShape)
-                    .background(MaterialTheme.colorScheme.errorContainer),
-                contentAlignment = Alignment.Center,
-            ) {
-                Icon(
-                    imageVector = Icons.Filled.Lock,
-                    contentDescription = null,
-                    tint = MaterialTheme.colorScheme.onErrorContainer,
-                    modifier = Modifier.size(24.dp),
-                )
-            }
-        }
-    }
-}
-
-/** One trust point: a tonal icon chip on the left, title + supporting text right. */
-@Composable
-private fun BenefitRow(icon: ImageVector, title: String, body: String) {
-    Row(
-        modifier = Modifier.fillMaxWidth(),
-        verticalAlignment = Alignment.CenterVertically,
-    ) {
-        Box(
-            modifier = Modifier
-                .size(44.dp)
-                .clip(CircleShape)
-                .background(MaterialTheme.colorScheme.secondaryContainer),
-            contentAlignment = Alignment.Center,
-        ) {
-            Icon(
-                imageVector = icon,
-                contentDescription = null,
-                tint = MaterialTheme.colorScheme.onSecondaryContainer,
-                modifier = Modifier.size(22.dp),
-            )
-        }
-        Spacer(Modifier.width(Space.sm))
-        Column(modifier = Modifier.weight(1f)) {
-            Text(text = title, style = MaterialTheme.typography.titleMedium)
-            Text(
-                text = body,
-                style = MaterialTheme.typography.bodyMedium,
-                color = MaterialTheme.colorScheme.onSurfaceVariant,
-            )
-        }
-    }
-}
-
@Composable
 private fun PrivacyFootnote() {
    Row(
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/ReminderOnboardingScreen.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/ReminderOnboardingScreen.kt
@@ -0,0 +1,138 @@
+package de.jeanlucmakiola.calendula.ui.permission
+
+import android.Manifest
+import android.os.Build
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.NotificationsActive
+import androidx.compose.material.icons.filled.ContentCopy
+import androidx.compose.material.icons.filled.Tune
+import androidx.compose.material3.Button
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import de.jeanlucmakiola.calendula.R
+
+/**
+ * One-time onboarding step after the calendar grant (v1.4): explains that
+ * Calendula delivers reminder notifications itself, warns about duplicates
+ * when a second calendar app has notifications on, and requests
+ * `POST_NOTIFICATIONS` (a system dialog on API 33+ only; minSdk is 29).
+ *
+ * Reminders default ON: [onFinished] gets true from the primary action even
+ * if the system dialog is declined — the OS permission is the real gate, and
+ * the Settings toggle re-requests it. "Not now" turns the in-app toggle off.
+ */
+@Composable
+fun ReminderOnboardingScreen(
+    onFinished: (remindersEnabled: Boolean) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val launcher = rememberLauncherForActivityResult(
+        contract = ActivityResultContracts.RequestPermission(),
+    ) { onFinished(true) }
+
+    OnboardingScaffold(
+        modifier = modifier,
+        hero = { BellHero() },
+        actions = {
+            Button(
+                onClick = {
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+                        launcher.launch(Manifest.permission.POST_NOTIFICATIONS)
+                    } else {
+                        onFinished(true)
+                    }
+                },
+                modifier = Modifier.fillMaxWidth().height(56.dp),
+            ) {
+                Text(
+                    text = stringResource(R.string.reminder_onboarding_enable_button),
+                    style = MaterialTheme.typography.titleMedium,
+                )
+            }
+            TextButton(
+                onClick = { onFinished(false) },
+                modifier = Modifier.fillMaxWidth(),
+            ) {
+                Text(stringResource(R.string.reminder_onboarding_skip_button))
+            }
+        },
+    ) {
+        Text(
+            text = stringResource(R.string.app_name).uppercase(),
+            style = MaterialTheme.typography.labelLarge,
+            color = MaterialTheme.colorScheme.primary,
+            letterSpacing = 2.sp,
+        )
+        Spacer(Modifier.height(OnboardingSpace.xs))
+        Text(
+            text = stringResource(R.string.reminder_onboarding_title),
+            style = MaterialTheme.typography.headlineMedium,
+            textAlign = TextAlign.Center,
+        )
+        Spacer(Modifier.height(12.dp))
+        Text(
+            text = stringResource(R.string.reminder_onboarding_body),
+            style = MaterialTheme.typography.bodyLarge,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            textAlign = TextAlign.Center,
+        )
+
+        Spacer(Modifier.height(OnboardingSpace.xl))
+
+        BenefitRow(
+            icon = Icons.Filled.NotificationsActive,
+            title = stringResource(R.string.reminder_benefit_delivery_title),
+            body = stringResource(R.string.reminder_benefit_delivery_body),
+        )
+        Spacer(Modifier.height(OnboardingSpace.sm))
+        BenefitRow(
+            icon = Icons.Filled.ContentCopy,
+            title = stringResource(R.string.reminder_benefit_duplicates_title),
+            body = stringResource(R.string.reminder_benefit_duplicates_body),
+        )
+        Spacer(Modifier.height(OnboardingSpace.sm))
+        BenefitRow(
+            icon = Icons.Filled.Tune,
+            title = stringResource(R.string.reminder_benefit_reversible_title),
+            body = stringResource(R.string.reminder_benefit_reversible_body),
+        )
+    }
+}
+
+/** A bell in the brand squircle — same silhouette as the permission hero. */
+@Composable
+private fun BellHero() {
+    Box(
+        modifier = Modifier
+            .size(128.dp)
+            .clip(RoundedCornerShape(34.dp))
+            .background(MaterialTheme.colorScheme.primaryContainer),
+        contentAlignment = Alignment.Center,
+    ) {
+        Icon(
+            imageVector = Icons.Filled.NotificationsActive,
+            contentDescription = null,
+            tint = MaterialTheme.colorScheme.onPrimaryContainer,
+            modifier = Modifier.size(56.dp),
+        )
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/ReminderOnboardingViewModel.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/permission/ReminderOnboardingViewModel.kt
@@ -0,0 +1,39 @@
+package de.jeanlucmakiola.calendula.ui.permission
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import dagger.hilt.android.lifecycle.HiltViewModel
+import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.launch
+import javax.inject.Inject
+
+/**
+ * Gates the one-time reminder onboarding step (v1.4) shown after the calendar
+ * grant. [onboardingDone] is null until DataStore's first emission so the
+ * step neither flashes for users who completed it nor gets skipped.
+ */
+@HiltViewModel
+class ReminderOnboardingViewModel @Inject constructor(
+    private val prefs: SettingsPrefs,
+) : ViewModel() {
+
+    val onboardingDone: StateFlow<Boolean?> = prefs.reminderOnboardingDone
+        .map { done -> done as Boolean? }
+        .stateIn(
+            scope = viewModelScope,
+            started = SharingStarted.WhileSubscribed(5_000L),
+            initialValue = null,
+        )
+
+    /** Close the step, recording whether reminder notifications stay on. */
+    fun finish(remindersEnabled: Boolean) {
+        viewModelScope.launch {
+            prefs.setRemindersEnabled(remindersEnabled)
+            prefs.setReminderOnboardingDone()
+        }
+    }
+}
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsScreen.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsScreen.kt
@@ -1,7 +1,12 @@
 package de.jeanlucmakiola.calendula.ui.settings

+import android.Manifest
 import android.content.Intent
+import android.content.pm.PackageManager
+import android.os.Build
 import androidx.activity.compose.BackHandler
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
 import androidx.core.net.toUri
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
@@ -42,6 +47,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
+import androidx.core.content.ContextCompat
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.R
@@ -128,6 +134,13 @@ fun SettingsScreen(
                )
            }

+            HorizontalDivider(Modifier.padding(vertical = 8.dp))
+            SectionHeader(stringResource(R.string.settings_section_notifications))
+            RemindersRow(
+                checked = state.remindersEnabled,
+                onCheckedChange = viewModel::setRemindersEnabled,
+            )
+
            HorizontalDivider(Modifier.padding(vertical = 8.dp))
            SectionHeader(stringResource(R.string.settings_section_language))
            LanguageRow()
@@ -249,6 +262,55 @@ private fun DynamicColorRow(
    }
 }

+/**
+ * Reminder-notifications toggle (v1.4), mirroring the onboarding step.
+ * Turning it on re-requests `POST_NOTIFICATIONS` when missing (API 33+) —
+ * the pref is set either way; the OS permission is the real gate.
+ */
+@Composable
+private fun RemindersRow(
+    checked: Boolean,
+    onCheckedChange: (Boolean) -> Unit,
+) {
+    val context = LocalContext.current
+    val launcher = rememberLauncherForActivityResult(
+        contract = ActivityResultContracts.RequestPermission(),
+    ) { /* The pref is already on; a denial just leaves the OS gate shut. */ }
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(horizontal = 24.dp, vertical = 12.dp),
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        Column(Modifier.weight(1f)) {
+            Text(
+                text = stringResource(R.string.settings_reminders),
+                style = MaterialTheme.typography.bodyLarge,
+            )
+            Text(
+                text = stringResource(R.string.settings_reminders_hint),
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+        Spacer(Modifier.width(16.dp))
+        Switch(
+            checked = checked,
+            onCheckedChange = { enabled ->
+                onCheckedChange(enabled)
+                val needsPermission = enabled &&
+                    Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
+                    ContextCompat.checkSelfPermission(
+                        context, Manifest.permission.POST_NOTIFICATIONS,
+                    ) != PackageManager.PERMISSION_GRANTED
+                if (needsPermission) {
+                    launcher.launch(Manifest.permission.POST_NOTIFICATIONS)
+                }
+            },
+        )
+    }
+}
+
@Composable
 private fun AboutSection() {
    val context = LocalContext.current
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsUiState.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsUiState.kt
@@ -18,4 +18,6 @@ data class SettingsUiState(
    val weekStart: WeekStartPref = WeekStartPref.AUTO,
    /** Optional event-form fields shown by default (rest behind "more fields"). */
    val defaultFormFields: Set<EventFormField> = SettingsPrefs.DEFAULT_FORM_FIELDS,
+    /** Whether Calendula posts reminder notifications (v1.4). */
+    val remindersEnabled: Boolean = true,
 )
--- a/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsViewModel.kt
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsViewModel.kt
@@ -28,13 +28,15 @@ class SettingsViewModel @Inject constructor(
            prefs.dynamicColor,
            prefs.weekStart,
            prefs.defaultFormFields,
-        ) { theme, dynamic, weekStart, formFields ->
+            prefs.remindersEnabled,
+        ) { theme, dynamic, weekStart, formFields, reminders ->
            SettingsUiState(
                themeMode = theme,
                dynamicColor = dynamic && dynamicColorAvailable,
                dynamicColorAvailable = dynamicColorAvailable,
                weekStart = weekStart,
                defaultFormFields = formFields,
+                remindersEnabled = reminders,
            )
        }.stateIn(
            scope = viewModelScope,
@@ -57,4 +59,8 @@ class SettingsViewModel @Inject constructor(
    fun setFormFieldDefault(field: EventFormField, enabled: Boolean) {
        viewModelScope.launch { prefs.setFormFieldDefault(field, enabled) }
    }
+
+    fun setRemindersEnabled(enabled: Boolean) {
+        viewModelScope.launch { prefs.setRemindersEnabled(enabled) }
+    }
 }
--- a/app/src/main/res/drawable/ic_notification.xml
+++ b/app/src/main/res/drawable/ic_notification.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Monochrome status-bar mark: Material "event" calendar glyph. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/colorControlNormal">
+    <path
+        android:fillColor="@android:color/white"
+        android:pathData="M19,3h-1V1h-2v2H8V1H6v2H5C3.89,3 3.01,3.9 3.01,5L3,19c0,1.1 0.89,2 2,2h14c1.1,0 2,-0.9 2,-2V5C21,3.9 20.1,3 19,3zM19,19H5V8h14V19zM7,10h5v5H7V10z" />
+</vector>
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -82,6 +82,16 @@
    <string name="event_edit_availability">Verfügbarkeit</string>
    <string name="event_edit_visibility">Sichtbarkeit</string>

+    <!-- Termin-Formular — Speicher-Konflikt (v2.0) -->
+    <string name="event_edit_conflict_title">Termin wurde extern geändert</string>
+    <string name="event_edit_conflict_body">Während du bearbeitet hast, wurde dieser Termin anderswo geändert — durch Synchronisierung oder eine andere App. Was soll mit deinen Änderungen passieren?</string>
+    <string name="event_edit_conflict_overwrite">Meine Änderungen speichern</string>
+    <string name="event_edit_conflict_overwrite_hint">Nur von dir bearbeitete Felder überschreiben die externe Änderung</string>
+    <string name="event_edit_conflict_discard">Meine Änderungen verwerfen</string>
+    <string name="event_edit_conflict_discard_hint">Der Termin bleibt, wie er jetzt ist</string>
+    <string name="event_edit_gone_title">Termin wurde gelöscht</string>
+    <string name="event_edit_gone_body">Dieser Termin wurde zwischenzeitlich gelöscht, etwa auf einem anderen Gerät. Deine Änderungen können nicht mehr gespeichert werden.</string>
+
    <!-- Termin-Formular — Wiederholungs-Picker (v1.3) -->
    <string name="event_edit_recurrence_none">Wiederholt sich nicht</string>
    <string name="event_edit_recurrence_custom">Benutzerdefiniert</string>
@@ -159,6 +169,20 @@
    <!-- Geteilte Event-Strings -->
    <string name="event_untitled">(Ohne Titel)</string>

+    <!-- Erinnerungs-Benachrichtigungen (v1.4) -->
+    <string name="reminder_channel_name">Termin-Erinnerungen</string>
+    <string name="reminder_channel_description">Benachrichtigungen zu den Erinnerungszeiten deiner Termine</string>
+    <string name="reminder_onboarding_title">Keinen Termin mehr verpassen</string>
+    <string name="reminder_onboarding_body">Android zeigt Termin-Erinnerungen nicht von selbst — das muss eine Kalender-App tun. Überlass Calendula den Job.</string>
+    <string name="reminder_benefit_delivery_title">Erinnerungen, zugestellt</string>
+    <string name="reminder_benefit_delivery_body">Jede Erinnerung an deinen Terminen kommt pünktlich als Benachrichtigung an.</string>
+    <string name="reminder_benefit_duplicates_title">Noch eine zweite Kalender-App?</string>
+    <string name="reminder_benefit_duplicates_body">Wenn eine andere App ebenfalls Erinnerungen zeigt, siehst du sie doppelt — schalte sie dort oder hier ab.</string>
+    <string name="reminder_benefit_reversible_title">Jederzeit änderbar</string>
+    <string name="reminder_benefit_reversible_body">Der Schalter liegt in den Einstellungen unter Benachrichtigungen.</string>
+    <string name="reminder_onboarding_enable_button">Erinnerungen einschalten</string>
+    <string name="reminder_onboarding_skip_button">Später</string>
+
    <!-- View-Switcher (M1) -->
    <string name="view_month">Monat</string>
    <string name="view_week">Woche</string>
@@ -183,6 +207,9 @@
    <string name="settings_week_start_sunday">Sonntag</string>
    <string name="settings_section_event_form">Termin-Formular</string>
    <string name="settings_form_fields_hint">Standardmäßig angezeigte Felder — alles Weitere liegt hinter \"Weitere Felder\"</string>
+    <string name="settings_section_notifications">Benachrichtigungen</string>
+    <string name="settings_reminders">Termin-Erinnerungen</string>
+    <string name="settings_reminders_hint">Erinnerungen doppelt? Eine andere Kalender-App zeigt sie ebenfalls — schalte sie in einer der beiden ab.</string>
    <string name="settings_section_language">Sprache</string>
    <string name="settings_language">App-Sprache</string>
    <string name="settings_language_auto">Systemstandard</string>
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -83,6 +83,16 @@
    <string name="event_edit_availability">Availability</string>
    <string name="event_edit_visibility">Visibility</string>

+    <!-- Event form — save conflict (v2.0) -->
+    <string name="event_edit_conflict_title">Event changed elsewhere</string>
+    <string name="event_edit_conflict_body">While you were editing, this event was changed — by sync or another app. What should happen to your changes?</string>
+    <string name="event_edit_conflict_overwrite">Save my changes</string>
+    <string name="event_edit_conflict_overwrite_hint">Only fields you edited overwrite the outside change</string>
+    <string name="event_edit_conflict_discard">Discard my changes</string>
+    <string name="event_edit_conflict_discard_hint">The event stays as it is now</string>
+    <string name="event_edit_gone_title">Event deleted</string>
+    <string name="event_edit_gone_body">This event was deleted in the meantime, for example on another device. Your changes can no longer be saved.</string>
+
    <!-- Event form — recurrence picker (v1.3) -->
    <string name="event_edit_recurrence_none">Does not repeat</string>
    <string name="event_edit_recurrence_custom">Custom</string>
@@ -160,6 +170,20 @@
    <!-- Shared event strings -->
    <string name="event_untitled">(No title)</string>

+    <!-- Reminder notifications (v1.4) -->
+    <string name="reminder_channel_name">Event reminders</string>
+    <string name="reminder_channel_description">Notifications at the reminder times of your events</string>
+    <string name="reminder_onboarding_title">Never miss an event</string>
+    <string name="reminder_onboarding_body">Android doesn\'t show event reminders by itself — a calendar app has to. Let Calendula take that job.</string>
+    <string name="reminder_benefit_delivery_title">Reminders, delivered</string>
+    <string name="reminder_benefit_delivery_body">Every reminder on your events arrives as a notification, right on time.</string>
+    <string name="reminder_benefit_duplicates_title">Using a second calendar app?</string>
+    <string name="reminder_benefit_duplicates_body">If another app also posts reminders, you\'ll see them twice — turn them off there or here.</string>
+    <string name="reminder_benefit_reversible_title">Change it anytime</string>
+    <string name="reminder_benefit_reversible_body">The switch lives in Settings, under Notifications.</string>
+    <string name="reminder_onboarding_enable_button">Turn on reminders</string>
+    <string name="reminder_onboarding_skip_button">Not now</string>
+
    <!-- View switcher (M1) -->
    <string name="view_month">Month</string>
    <string name="view_week">Week</string>
@@ -184,6 +208,9 @@
    <string name="settings_week_start_sunday">Sunday</string>
    <string name="settings_section_event_form">New event form</string>
    <string name="settings_form_fields_hint">Fields shown by default — everything else sits behind \"More fields\"</string>
+    <string name="settings_section_notifications">Notifications</string>
+    <string name="settings_reminders">Event reminders</string>
+    <string name="settings_reminders_hint">Seeing reminders twice? Another calendar app is posting them too — turn them off in one of the two.</string>
    <string name="settings_section_language">Language</string>
    <string name="settings_language">App language</string>
    <string name="settings_language_auto">System default</string>
--- a/app/src/test/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefsTest.kt
+++ b/app/src/test/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefsTest.kt
@@ -100,6 +100,27 @@ class SettingsPrefsTest {
        assertThat(prefs.defaultFormFields.first()).containsExactly(EventFormField.Location)
    }

+    @Test
+    fun `reminders default to enabled, onboarding to not done`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        assertThat(prefs.remindersEnabled.first()).isTrue()
+        assertThat(prefs.reminderOnboardingDone.first()).isFalse()
+    }
+
+    @Test
+    fun `reminders toggle round-trips`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        prefs.setRemindersEnabled(false)
+        assertThat(prefs.remindersEnabled.first()).isFalse()
+    }
+
+    @Test
+    fun `reminder onboarding completes one-way`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        prefs.setReminderOnboardingDone()
+        assertThat(prefs.reminderOnboardingDone.first()).isTrue()
+    }
+
    @Test
    fun `explicit week-start prefs resolve regardless of locale`() {
        assertThat(WeekStartPref.MONDAY.resolveFirstDay(Locale.US)).isEqualTo(DayOfWeek.MONDAY)
--- a/app/src/test/java/de/jeanlucmakiola/calendula/data/reminders/ReminderTimeTextTest.kt
+++ b/app/src/test/java/de/jeanlucmakiola/calendula/data/reminders/ReminderTimeTextTest.kt
@@ -0,0 +1,85 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+import java.time.LocalDate
+import java.time.LocalDateTime
+import java.time.ZoneId
+import java.time.ZoneOffset
+import java.util.Locale
+
+class ReminderTimeTextTest {
+
+    private val berlin = ZoneId.of("Europe/Berlin")
+
+    private fun millisAt(dateTime: LocalDateTime, zone: ZoneId): Long =
+        dateTime.atZone(zone).toInstant().toEpochMilli()
+
+    private fun utcMidnight(date: LocalDate): Long =
+        date.atStartOfDay(ZoneOffset.UTC).toInstant().toEpochMilli()
+
+    @Test
+    fun `timed event on one day shows just the time range`() {
+        val text = reminderTimeText(
+            beginMillis = millisAt(LocalDateTime.of(2026, 6, 11, 9, 30), berlin),
+            endMillis = millisAt(LocalDateTime.of(2026, 6, 11, 10, 0), berlin),
+            isAllDay = false,
+            zone = berlin,
+            locale = Locale.GERMANY,
+        )
+        assertThat(text).isEqualTo("09:30 – 10:00")
+    }
+
+    @Test
+    fun `timed event crossing midnight includes both dates`() {
+        val text = reminderTimeText(
+            beginMillis = millisAt(LocalDateTime.of(2026, 6, 11, 23, 30), berlin),
+            endMillis = millisAt(LocalDateTime.of(2026, 6, 12, 0, 30), berlin),
+            isAllDay = false,
+            zone = berlin,
+            locale = Locale.GERMANY,
+        )
+        assertThat(text).contains("11.06.2026")
+        assertThat(text).contains("12.06.2026")
+        assertThat(text).contains("23:30")
+    }
+
+    @Test
+    fun `all-day single day shows one date, read in UTC`() {
+        val text = reminderTimeText(
+            beginMillis = utcMidnight(LocalDate.of(2026, 6, 11)),
+            endMillis = utcMidnight(LocalDate.of(2026, 6, 12)),
+            isAllDay = true,
+            // Zone must not matter for all-day events: UTC midnight is
+            // 02:00 in Berlin — naive local reading would shift the day.
+            zone = berlin,
+            locale = Locale.GERMANY,
+        )
+        assertThat(text).isEqualTo("11.06.2026")
+    }
+
+    @Test
+    fun `all-day multi-day shows the last covered day, not the exclusive end`() {
+        val text = reminderTimeText(
+            beginMillis = utcMidnight(LocalDate.of(2026, 6, 11)),
+            endMillis = utcMidnight(LocalDate.of(2026, 6, 13)),
+            isAllDay = true,
+            zone = berlin,
+            locale = Locale.GERMANY,
+        )
+        assertThat(text).isEqualTo("11.06.2026 – 12.06.2026")
+    }
+
+    @Test
+    fun `degenerate all-day range never renders an inverted span`() {
+        val day = utcMidnight(LocalDate.of(2026, 6, 11))
+        val text = reminderTimeText(
+            beginMillis = day,
+            endMillis = day,
+            isAllDay = true,
+            zone = berlin,
+            locale = Locale.GERMANY,
+        )
+        assertThat(text).isEqualTo("11.06.2026")
+    }
+}
--- a/app/src/test/java/de/jeanlucmakiola/calendula/domain/EventFormTest.kt
+++ b/app/src/test/java/de/jeanlucmakiola/calendula/domain/EventFormTest.kt
@@ -112,21 +112,24 @@ class EventFormTest {
        reminders: List<Reminder> = emptyList(),
        availability: Availability = Availability.Busy,
        accessLevel: AccessLevel = AccessLevel.Default,
+        rowStart: Long = 0L,
+        rowEnd: Long = 0L,
+        attendees: List<Attendee> = emptyList(),
    ): EventDetail = EventDetail(
        instance = EventInstance(
            instanceId = 1L,
            eventId = 1L,
            calendarId = 7L,
            title = title,
-            start = Instant.fromEpochMilliseconds(0L),
-            end = Instant.fromEpochMilliseconds(0L),
+            start = Instant.fromEpochMilliseconds(rowStart),
+            end = Instant.fromEpochMilliseconds(rowEnd),
            isAllDay = isAllDay,
            color = 0,
            location = location,
        ),
        description = description,
        organizer = null,
-        attendees = emptyList(),
+        attendees = attendees,
        rrule = rrule,
        reminders = reminders,
        availability = availability,
@@ -177,6 +180,41 @@ class EventFormTest {
        assertThat(prefilled.rrule).isEqualTo("FREQ=WEEKLY")
    }

+    @Test
+    fun `snapshots of an unchanged event are equal`() {
+        val a = detail().toEditSnapshot(0L, 3_600_000L, berlin)
+        val b = detail().toEditSnapshot(0L, 3_600_000L, berlin)
+        assertThat(b).isEqualTo(a)
+    }
+
+    @Test
+    fun `an external field change makes snapshots differ`() {
+        val loaded = detail().toEditSnapshot(0L, 3_600_000L, berlin)
+        val fresh = detail(title = "Stand-up (moved)").toEditSnapshot(0L, 3_600_000L, berlin)
+        assertThat(fresh).isNotEqualTo(loaded)
+    }
+
+    @Test
+    fun `an external time move is caught by the row times the form cannot see`() {
+        // Both snapshots are taken for the same tapped occurrence, so the
+        // *forms* derive identical times — only rowStart/rowEnd betray the move.
+        val loaded = detail(rrule = "FREQ=WEEKLY", rowStart = 0L)
+            .toEditSnapshot(0L, 3_600_000L, berlin)
+        val fresh = detail(rrule = "FREQ=WEEKLY", rowStart = 86_400_000L)
+            .toEditSnapshot(0L, 3_600_000L, berlin)
+        assertThat(fresh.form).isEqualTo(loaded.form)
+        assertThat(fresh).isNotEqualTo(loaded)
+    }
+
+    @Test
+    fun `changes the form cannot write do not fake a conflict`() {
+        val loaded = detail().toEditSnapshot(0L, 3_600_000L, berlin)
+        val fresh = detail(
+            attendees = listOf(Attendee("Ada", "ada@example.org", AttendeeStatus.Accepted)),
+        ).toEditSnapshot(0L, 3_600_000L, berlin)
+        assertThat(fresh).isEqualTo(loaded)
+    }
+
    @Test
    fun `populatedFields reports exactly the sections holding values`() {
        val empty = form().copy(location = "", description = "")
--- a/docs/superpowers/plans/2026-06-11-03-write-support.md
+++ b/docs/superpowers/plans/2026-06-11-03-write-support.md
@@ -47,8 +47,8 @@ Domain bleibt pure Kotlin.
 |---|---|---|
 | v1.1 | Write-Fundament: `WRITE_CALENDAR`, `canModifyContents`, Delete (Serie + einzelnes Vorkommen) | ausgeliefert (v1.1.0, 2026-06-11) |
 | v1.2 | Create: Event-Formular (Titel, Kalender, ganztägig, Start/Ende, Ort, Beschreibung), FAB, Default-Kalender-Pref | ausgeliefert (v1.2.0, 2026-06-11) |
-| v1.3 | Edit: Formular wiederverwendet, Serien-Edit, Reminder-Edit, einfacher Recurrence-Picker | implementiert (Release wartet auf On-Device-Review) |
-| v2.0 | Quick-Add, Occurrence-Edit, Konflikt-Dialog, Polish-Pass, Release | offen |
+| v1.3 | Edit: Formular wiederverwendet, Serien-Edit, Reminder-Edit, einfacher Recurrence-Picker | ausgeliefert (v1.3.0, 2026-06-11) |
+| v2.0 | Konflikt-Dialog, Polish-Pass (Store-Copy, Screenshots), Release | ausgeliefert (v2.0.0, 2026-06-11) |

 ## v1.1 — Write-Fundament + Delete

@@ -180,9 +180,25 @@ Domain bleibt pure Kotlin.
 Bewusst nicht in v1.3 (→ v2.0): Konflikt-Dialog, Kalender-Wechsel beim
 Bearbeiten (Sync-Adapter-Minenfeld, sperren auch alle Stock-Apps).

-## v2.0 — Abschluss (Skizze)
+## v2.0 — Abschluss (Scope-Recut 2026-06-11, nach v1.4)

- Quick-Add-Sheet (Titel + Zeit, Rest Defaults)
- Occurrence-Edit (Exception mit geänderten Werten)
- Konflikt-Dialog beim Speichern
- Changelog, F-Droid-Metadaten, Release-Tag
+- ~~Quick-Add-Sheet (Titel + Zeit, Rest Defaults)~~ — **gestrichen**: das
+  Formular öffnet bereits vorbefüllt (sichtbarer Tag, zuletzt benutzter
+  Kalender, optionale Felder versteckt); der Sheet spart nur einen
+  Screen-Übergang und kostet eine zweite Create-Surface. Nur bei
+  Praxis-Feedback wieder aufnehmen
+- ~~Occurrence-Edit (Exception mit geänderten Werten)~~ — schon in v1.3
+  ausgeliefert (vorgezogen)
+- [x] Konflikt-Dialog beim Speichern (Leitentscheidung 5): `EditSnapshot`
+      (Formular + rohe Row-Zeiten) wird beim Laden gemerkt und vor dem
+      Schreiben gegen einen frischen Read verglichen; Abweichung parkt den
+      Save in `AwaitingConflict` (Überschreiben/Verwerfen/Abbrechen,
+      OptionCard-Stil), gelöschtes Event → `Gone`-Dialog. "Überschreiben"
+      schreibt weiterhin nur dirty Felder
+- Kalender-Wechsel beim Bearbeiten → v3-Backlog (copy+delete-Modell)
+- [x] Polish: F-Droid-Description + README auf Write-Support + Reminder
+      aktualisiert (DE+EN)
+- [x] F-Droid-Screenshots (de-DE + en-US, je 6: Woche/Monat/Tag/Detail/
+      Formular/Onboarding) — mit Demo-Kalendern auf dem Gerät aufgenommen
+- [x] Changelog, Release-Tag v2.0.0 (ausgeliefert 2026-06-11 — Milestone 2
+      damit abgeschlossen)
--- a/docs/superpowers/plans/2026-06-11-04-reminder-notifications.md
+++ b/docs/superpowers/plans/2026-06-11-04-reminder-notifications.md
@@ -0,0 +1,119 @@
+# Calendula - Plan 04: Reminder Notifications (v1.4)
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Calendula stellt Erinnerungen selbst als Notification zu (Etar-Modell).
+Der Provider plant die Alarme und broadcastet
+`android.intent.action.EVENT_REMINDER` — die sichtbare Notification postet er
+**nicht**, das muss eine Kalender-App tun. Für Nutzer, deren einzige
+Kalender-App Calendula ist, ist das essenziell, kein Nice-to-have.
+`./gradlew lint test assembleDebug` bleibt grün; Release erst nach
+On-Device-Review.
+
+**Architecture:** Eigenes kleines Datenmodul `data/reminders/` neben
+`data/calendar/` — der Receiver braucht weder Repository noch Flows. Schichtung
+wie gehabt: `EventReminderReceiver` (Hilt-EntryPoint) →
+`ReminderAlertStore` (Interface, Android-Impl auf `CalendarAlerts`) →
+`ReminderNotifier` (NotificationManager). Domain bleibt pure Kotlin
+(`ReminderAlert`-Modell, JVM-testbare Textformatierung).
+
+**Recherche-Befunde (AOSP `CalendarAlarmManager` + Etar, 2026-06-11):**
+
+1. Der Provider legt `CalendarAlerts`-Rows **nur für `METHOD_ALERT`-Reminder**
+   an (AOSP-Query: `AND method=1`). Der im Roadmap-Eintrag geforderte
+   METHOD-Filter (E-Mail überspringen) passiert also schon upstream — wir
+   filtern nicht doppelt. Calendula schreibt eigene Reminder ohnehin als
+   `METHOD_ALERT`.
+2. Der Broadcast ist implizit (Action + `content://com.android.calendar/…`-URI,
+   Extra `alarmTime`). Etars Manifest-Receiver ist `exported="true"` mit
+   `<data android:scheme="content"/>` — das übernehmen wir (plus Host,
+   enger gefasst). Den URI-Inhalt werten wir nicht aus; wir queryen selbst
+   "fällig & noch SCHEDULED".
+3. Etar postet aus dem Zustand `SCHEDULED ∪ FIRED` und verwaltet Dismiss über
+   eigene Services. Wir vereinfachen: nur `STATE_SCHEDULED AND alarmTime <= now`
+   posten, danach best-effort auf `FIRED` setzen (braucht `WRITE_CALENDAR`;
+   `SecurityException` wird geschluckt). Weggewischte Notifications kommen so
+   nie wieder, ohne deleteIntent-Maschinerie: FIRED-Rows fassen wir nicht an.
+   Re-Broadcasts ohne Write-Recht ersetzen still (Tag pro Alert +
+   `setOnlyAlertOnce`).
+
+**Leitentscheidungen:**
+
+1. **Kein eigenes Alarm-Scheduling** (kein `SCHEDULE_EXACT_ALARM`, kein
+   `BOOT_COMPLETED`, kein WorkManager): Zustellung hängt am Provider-Broadcast.
+   Etars Zusatz-Maschinerie (eigener AlarmScheduler) kommt erst, wenn sich
+   Zuverlässigkeit auf echten Geräten als Problem zeigt (Roadmap: bewusst
+   verschoben, ebenso Snooze-/Dismiss-Actions und Battery-Exemption).
+2. **Toggle default ON, Onboarding-Schritt danach:** Nach dem Kalender-Grant
+   folgt ein zweiter Onboarding-Screen (gleiche Shell wie der Permission-
+   Screen): erklärt Reminder, warnt vor Duplikaten (zweite Kalender-App mit
+   aktiven Notifications), fragt `POST_NOTIFICATIONS` an (nur API 33+ zeigt
+   einen Dialog; minSdk 29). "Später" schaltet den Toggle aus. Der Schritt
+   erscheint genau einmal (`reminder_onboarding_done`-Pref) — auch für
+   v1.0–v1.3-Upgrader, die das Feature so entdecken.
+3. **Settings-Spiegel:** Abschnitt "Erinnerungen" mit demselben Toggle +
+   Duplikat-Hinweis. Einschalten fordert `POST_NOTIFICATIONS` kontextuell an,
+   wenn sie fehlt.
+4. **Tap öffnet das Event-Detail:** Notification-Intent trägt
+   eventId/begin/end; `MainActivity` wird `singleTop`, reicht den Key als
+   Compose-State an `CalendarHost` durch (gleiches LongArray-Key-Muster wie
+   der Detail-Overlay selbst).
+5. **Ein Kanal, einfache Inhalte:** Kanal "Erinnerungen"
+   (`IMPORTANCE_HIGH`), pro Alert eine Notification (Tag = Alert-Id):
+   Titel = Eventtitel (Fallback "(Ohne Titel)"), Text = Zeitspanne
+   (ganztägig: Datum, UTC gelesen) + Ort. Kein Grouping/Summary, kein
+   Vollbild-Alarm.
+
+---
+
+## Tasks
+
+**Manifest / Resourcen:**
+- [x] `POST_NOTIFICATIONS` ins Manifest; Receiver `.reminders.EventReminderReceiver`
+      `exported="true"`, Intent-Filter `EVENT_REMINDER` + `data scheme=content
+      host=com.android.calendar`; `MainActivity` → `launchMode="singleTop"`
+- [x] Monochromes Notification-Icon `drawable/ic_notification.xml`
+- [x] Strings DE+EN: Kanal, Onboarding-Copy, Settings-Abschnitt + Hinweis
+
+**Prefs:**
+- [x] `SettingsPrefs.remindersEnabled` (default **true**) + Setter;
+      `reminderOnboardingDone` (default false) + Setter; `SettingsPrefsTest`
+
+**Data layer (`data/reminders/`):**
+- [x] `ReminderAlert`-Modell (in `data/reminders/`, nicht domain — Alerts
+      erreichen nie einen Screen): alertId, eventId, begin/end als Millis,
+      title, location, isAllDay
+- [x] `ReminderAlertStore` (Interface) + `AndroidReminderAlertStore`:
+      `dueAlerts(nowMillis)` = `CalendarAlerts` mit
+      `STATE_SCHEDULED AND ALARM_TIME <= now`;
+      `markFired(ids, nowMillis)` setzt STATE/RECEIVED_TIME/NOTIFY_TIME,
+      `SecurityException` → Log (Write-Recht optional)
+- [x] `ReminderNotifier`: Kanal lazy anlegen, eine Notification pro Alert
+      (Tag = alertId, `setOnlyAlertOnce`, autoCancel, `when` = begin,
+      Category EVENT), Content-PendingIntent auf `MainActivity` mit
+      eventId/begin/end
+- [x] Zeitspannen-Text als pure Funktion (JVM-testbar) + Test
+
+**Receiver:**
+- [x] `EventReminderReceiver` (`@AndroidEntryPoint`): Action prüfen,
+      `goAsync()`; raus, wenn Pref aus, READ_CALENDAR fehlt oder
+      Notifications systemseitig geblockt; sonst posten → `markFired`
+
+**UI:**
+- [x] Onboarding-Shell aus `PermissionScreen` extrahieren
+      (`OnboardingScaffold` + BenefitRow, intern wiederverwendet)
+- [x] `NotificationOnboardingScreen` + ViewModel: Benefit-Rows (verpasst
+      nichts / Duplikat-Warnung), Primär-Button fordert `POST_NOTIFICATIONS`
+      (API 33+) und lässt den Toggle an, "Später" schaltet ihn aus; beide
+      setzen `reminder_onboarding_done`
+- [x] `RootScreen`: Kalender-Gate → Reminder-Schritt (einmalig) → `CalendarHost`
+- [x] `CalendarHost`: externer Detail-Key (Notification-Tap) wird wie ein
+      Event-Tap konsumiert; `MainActivity` parst Intent (onCreate +
+      onNewIntent) in Compose-State
+- [x] Settings: Abschnitt "Benachrichtigungen" — Toggle (mit kontextuellem
+      Permission-Request beim Einschalten) + Duplikat-Hinweistext
+
+**Abschluss:**
+- [x] `./gradlew lint test assembleDebug` grün
+- [x] CHANGELOG (`[Unreleased]`), ROADMAP-Status; **kein** Tag/Release vor
+      On-Device-Review
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/description.txt
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/description.txt
@@ -1,12 +1,17 @@
-Calendula ist eine moderne, quelloffene Kalender-App für Android. Sie liest
-direkt aus dem System-Kalender-Provider — jede Quelle, die mit deinem Gerät
-synchronisiert ist (Nextcloud über DAVx5, Google, lokal, WebCal-Subscriptions)
-erscheint automatisch.
+Calendula ist eine moderne, quelloffene Kalender-App für Android. Sie
+arbeitet direkt auf dem System-Kalender-Provider — jede Quelle, die mit
+deinem Gerät synchronisiert ist (Nextcloud über DAVx5, Google, lokal,
+WebCal-Subscriptions), erscheint automatisch, und deine Änderungen
+synchronisieren auf demselben Weg zurück.
+
+Termine erstellen, bearbeiten und löschen — auch wiederkehrende, mit
+wählbarer Reichweite (nur dieser Termin / dieser und alle folgenden / ganze
+Serie) und einem einfachen Wiederholungs-Picker. Erinnerungen stellt
+Calendula selbst als Benachrichtigung zu — ein Tipp darauf öffnet den
+Termin.

 Der Unterschied liegt im Design: echtes Material 3 Expressive durchgehend,
 mit Dynamic Color, expressiven Animationen und neuen Shape-Sprachen.

-V1 ist read-only. Erstellen, Bearbeiten und Löschen von Events kommt mit V2.
-
-Datenschutz: keinerlei Telemetrie, kein Tracking, kein Netzwerkzugriff — deine
-Daten bleiben auf dem Gerät.
+Datenschutz: keinerlei Telemetrie, kein Tracking, kein Netzwerkzugriff —
+deine Daten bleiben auf dem Gerät.
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/01-week.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/01-week.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/02-month.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/02-month.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/03-day.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/03-day.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/04-detail.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/04-detail.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/05-edit.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/05-edit.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/06-onboarding.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/de-DE/phoneScreenshots/06-onboarding.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/description.txt
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/description.txt
@@ -1,11 +1,15 @@
-Calendula is a modern, open-source calendar app for Android. It reads from
-the system calendar provider, so any source synced to your device — Nextcloud
-via DAVx5, Google, local, WebCal subscriptions — shows up automatically.
+Calendula is a modern, open-source calendar app for Android. It works
+directly on the system calendar provider, so any source synced to your
+device — Nextcloud via DAVx5, Google, local, WebCal subscriptions — shows up
+automatically, and changes you make sync back the same way.

-The differentiator is the design: real Material 3 Expressive throughout, with
-dynamic color, expressive motion, and expressive shapes.
+Create, edit and delete events, including recurring events with scoped
+changes (only this event / this and all following / the whole series) and a
+simple repeat picker. Calendula also delivers your event reminders as
+notifications — tap one and you're on the event.

-V1 is read-only. Event creation, editing, and deletion are planned for V2.
+The differentiator is the design: real Material 3 Expressive throughout,
+with dynamic color, expressive motion, and expressive shapes.

 Privacy: zero telemetry, no analytics, no network access — your data never
 leaves the device.
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/01-week.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/01-week.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/02-month.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/02-month.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/03-day.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/03-day.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/04-detail.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/04-detail.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/05-edit.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/05-edit.png
--- a/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/06-onboarding.png
+++ b/fdroid-metadata/de.jeanlucmakiola.calendula/en-US/phoneScreenshots/06-onboarding.png
Author	SHA1	Message	Date
Jean-Luc Makiola	d028b70e6e	release: cut v2.0.0 — write support complete Some checks failed CI / ci (push) Failing after 1m7s Details Build and Release to F-Droid / ci (push) Successful in 5m47s Details Build and Release to F-Droid / build-and-deploy (push) Successful in 8m58s Details Version bumped to 2.0.0 / 13. No code changes beyond the version — 2.0.0 closes out Milestone 2 (write support, v1.1 through v2.0): the final slice is the save-conflict dialog (external change → overwrite/discard, external delete → informational close), plus the store refresh: descriptions and README describe write support and reminders, and fastlane screenshots (DE+EN, six each) ship for F-Droid. CHANGELOG [2.0.0] carries the details. Quick-add was cut from scope (the prefilled form covers it); calendar switching while editing moved to the v3 backlog. Both documented in the roadmap. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-06-11 22:15:50 +02:00
Jean-Luc Makiola	626623bb6e	feat(edit): conflict dialog on save + store metadata refresh (v2.0) No locking (plan 03, decision 5): openForEdit keeps an EditSnapshot — the prefilled form plus the raw Events-row times, which the form itself can't see (it derives its times from the tapped occurrence, so an externally moved event would otherwise stay invisible). Right before writing, performSave re-reads the event and compares snapshots: a mismatch parks the save in SaveUiState.AwaitingConflict carrying the already-chosen recurring scope, and the dialog offers overwrite / discard / cancel (OptionCard style). Overwrite still writes only dirty fields, so external changes to untouched fields survive either way. A deleted event lands in SaveUiState.Gone — an informational dialog that closes form and detail. Fields the form can't write (attendees, status, self response, reminder methods) are excluded from the comparison so sync noise can't fake a conflict. The load-time zone is pinned in the EditTarget so a device timezone change mid-edit can't either. Store metadata: F-Droid descriptions (DE+EN) and the README stop claiming read-only and now describe write support and reminder delivery. New fastlane phoneScreenshots (6 per locale: week/month/day/detail/form/ reminder onboarding), captured on-device against demo-only calendars. Tests: EditSnapshot equality (unchanged event, field change, row-time move the form can't see, non-writable changes stay quiet). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-06-11 22:14:27 +02:00
Jean-Luc Makiola	264b2a86c1	release: cut v1.4.0 — reminder notifications All checks were successful CI / ci (push) Successful in 8m7s Details Build and Release to F-Droid / build-and-deploy (push) Successful in 8m40s Details Build and Release to F-Droid / ci (push) Successful in 2m3s Details Version bumped to 1.4.0 / 12. No code changes beyond the version — 1.4.0 is the reviewed-and-approved reminder slice: the EVENT_REMINDER receiver posting due CalendarAlerts on a dedicated channel, tap-to-detail, the one-time onboarding step requesting POST_NOTIFICATIONS with the duplicate-reminders warning, and the Settings mirror. CHANGELOG [1.4.0] carries the details. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-06-11 21:24:10 +02:00
Jean-Luc Makiola	b03bd67678	feat(reminders): reminder notifications — EVENT_REMINDER receiver, onboarding step, settings toggle (v1.4) Calendula now posts event reminders itself (the Etar model): the provider schedules the alarms and broadcasts EVENT_REMINDER, but a calendar app must turn them into visible notifications — essential for users whose only calendar app this is. A manifest-registered, exported receiver (data scheme content://com.android.calendar) wakes us at reminder time; no foreground service, no own alarm scheduling. Delivery path (data/reminders/): EventReminderReceiver (Hilt, goAsync) → ReminderAlertStore queries CalendarAlerts for STATE_SCHEDULED rows with ALARM_TIME <= now → ReminderNotifier posts one notification per alert on a dedicated high-importance channel, then best-effort marks rows FIRED (needs WRITE_CALENDAR; without it a re-broadcast silently replaces — tag per alert + setOnlyAlertOnce). Swiped notifications never return: FIRED rows are never re-queried, so no dismiss-intent machinery. Research (AOSP CalendarAlarmManager): the provider creates alert rows only for METHOD_ALERT reminders, so the email-reminder filter happens upstream. Tapping opens the event's detail screen: MainActivity is singleTop now, parses eventId/begin/end extras (onCreate + onNewIntent) into Compose state, and CalendarHost consumes the key exactly like an event tap. Onboarding gained a one-time second step after the calendar grant (shared OnboardingScaffold extracted from PermissionScreen): explains delivery, warns that a second calendar app with notifications on duplicates reminders, requests POST_NOTIFICATIONS (dialog on API 33+ only; minSdk 29). "Not now" turns the feature off; reminders default ON. Settings mirrors the toggle in a new Notifications section with the duplicate hint, and re-requests the permission when enabling. Strings DE+EN. Deliberately deferred (roadmap): snooze/dismiss actions, BOOT_COMPLETED / exact-alarm scheduling, battery-exemption prompts. Tests: reminderTimeText (all-day UTC-midnight reading, exclusive end day, midnight-crossing ranges), reminders/onboarding pref round-trips. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-06-11 21:23:34 +02:00