diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 6bdb93d..2caa391 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -5,6 +5,7 @@ agp = "9.2.1"
 kotlin = "2.3.21"
 coreKtx = "1.19.0"
 appcompat = "1.7.1"
+activityCompose = "1.13.0"
 composeBom = "2026.05.01"
 # Material 3 Expressive APIs live in the 1.5 alpha line; pinned to override the BOM.
 material3 = "1.5.0-alpha21"
@@ -15,6 +16,7 @@ truth = "1.4.5"
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
 androidx-appcompat = { group = "androidx.appcompat", name = "appcompat", version.ref = "appcompat" }
+androidx-activity-compose = { group = "androidx.activity", name = "activity-compose", version.ref = "activityCompose" }
 androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "composeBom" }
 androidx-ui = { group = "androidx.compose.ui", name = "ui" }
 androidx-foundation = { group = "androidx.compose.foundation", name = "foundation" }
diff --git a/identity/build.gradle.kts b/identity/build.gradle.kts
index c21297b..9af4f6f 100644
--- a/identity/build.gradle.kts
+++ b/identity/build.gradle.kts
@@ -36,4 +36,6 @@ dependencies {
     implementation(libs.androidx.ui)
     implementation(libs.androidx.foundation)
     implementation(libs.androidx.material3)
+    // activity-compose for PredictiveBackHandler + BackEventCompat (the back-gesture peek).
+    implementation(libs.androidx.activity.compose)
 }
diff --git a/identity/src/main/kotlin/de/jeanlucmakiola/floret/identity/Motion.kt b/identity/src/main/kotlin/de/jeanlucmakiola/floret/identity/Motion.kt
new file mode 100644
index 0000000..c02c1de
--- /dev/null
+++ b/identity/src/main/kotlin/de/jeanlucmakiola/floret/identity/Motion.kt
@@ -0,0 +1,87 @@
+package de.jeanlucmakiola.floret.identity
+
+import android.provider.Settings
+import androidx.activity.BackEventCompat
+import androidx.activity.compose.PredictiveBackHandler
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.FastOutSlowInEasing
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.unit.dp
+import kotlin.coroutines.cancellation.CancellationException
+
+/**
+ * Whether the user has asked the system to remove animations (Settings →
+ * Accessibility → "Remove animations", which sets the global animator duration
+ * scale to 0). Compose animations do *not* honour this platform flag on their
+ * own, so the shared motion helpers check it and fall back to no spatial
+ * movement — respecting the vestibular intent of the setting while keeping state
+ * changes legible.
+ *
+ * Read once at composition; the scale changes rarely and only takes full effect
+ * after a process restart anyway.
+ */
+@Composable
+fun rememberReduceMotion(): Boolean {
+    val resolver = LocalContext.current.contentResolver
+    return remember(resolver) {
+        Settings.Global.getFloat(resolver, Settings.Global.ANIMATOR_DURATION_SCALE, 1f) == 0f
+    }
+}
+
+/**
+ * The standard Android predictive-back transform for a full-screen surface: as
+ * the back gesture is dragged, the surface scales toward ~90%, shifts toward the
+ * swiped edge and rounds its corners, previewing what's behind. Completing the
+ * gesture invokes [onBack]; cancelling springs it back.
+ *
+ * A drop-in replacement for a screen's own `BackHandler(onBack)` — register it
+ * once and apply the returned [Modifier] to that screen's root so the preview
+ * respects the same back semantics. Under reduced motion the visual preview is
+ * skipped (the back still works); on API < 34 the system delivers no progress,
+ * so it degrades to a plain back. Shared so the family's apps preview the same
+ * way.
+ *
+ * @param enabled gate the handler — e.g. set false while a screen's own inner
+ *   back (a sub-section) should take the gesture instead.
+ */
+@Composable
+fun Modifier.predictiveBack(
+    onBack: () -> Unit,
+    enabled: Boolean = true,
+    reduceMotion: Boolean = rememberReduceMotion(),
+): Modifier {
+    val progress = remember { Animatable(0f) }
+    var fromLeftEdge by remember { mutableStateOf(true) }
+
+    PredictiveBackHandler(enabled = enabled) { events ->
+        try {
+            events.collect { event ->
+                fromLeftEdge = event.swipeEdge == BackEventCompat.EDGE_LEFT
+                progress.snapTo(FastOutSlowInEasing.transform(event.progress))
+            }
+            onBack()
+            progress.snapTo(0f)
+        } catch (_: CancellationException) {
+            progress.animateTo(0f)
+        }
+    }
+
+    if (reduceMotion) return this
+    return this.graphicsLayer {
+        val p = progress.value
+        val scale = 1f - 0.1f * p
+        scaleX = scale
+        scaleY = scale
+        translationX = (if (fromLeftEdge) 1f else -1f) * 24.dp.toPx() * p
+        shape = RoundedCornerShape(32.dp.toPx() * p)
+        clip = p > 0f
+    }
+}