Release 0.1.1: critical bugfix sweep

Ships the two rounds of logical-flaw fixes: the evaluator overflow (never-alerted), silent alert channel, Apple phantom-tracker parser bug, stalker-auto-trust baseline flaw, ingestion throttle, lost-update race, unbounded tracker rows, and RSSI/evidence surfaced in the UI.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0187UiEtasyowhEBYs6s9iF5

app/build.gradle.kts

@@ -13,8 +13,8 @@ android {
         applicationId = "org.soulstone.vigil"
         minSdk = 26
         targetSdk = 35
-        versionCode = 1
-        versionName = "0.1.0"
+        versionCode = 2
+        versionName = "0.1.1"
     }
 
     // Fixed debug keystore committed to the repo (a debug key is non-secret — its

app/src/main/kotlin/org/soulstone/vigil/MainActivity.kt

@@ -49,8 +49,10 @@ class MainActivity : ComponentActivity() {
 
     private val permissionLauncher = registerForActivityResult(
         ActivityResultContracts.RequestMultiplePermissions()
-    ) { result ->
-        val granted = result.all { it.value }
+    ) { _ ->
+        // Scanning needs BLE + location; POST_NOTIFICATIONS is optional and must not
+        // block protection if the user declines it.
+        val granted = hasEssentialPermissions()
         permissionsGranted.value = granted
         if (granted) ScanService.start(this)
     }
@@ -59,7 +61,7 @@ class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
         settings = Settings.get(this)
         repo = TrackerRepository(VigilDatabase.get(this))
-        permissionsGranted.value = hasAllPermissions()
+        permissionsGranted.value = hasEssentialPermissions()
 
         setContent {
             VigilTheme {
@@ -86,6 +88,9 @@ class MainActivity : ComponentActivity() {
                     onSetSensitivity = { settings.setSensitivity(it) },
                     onApprove = { id, approved ->
                         lifecycleScope.launch { repo.setApproved(id, approved) }
+                    },
+                    onDistrust = { id ->
+                        lifecycleScope.launch { repo.clearBaseline(id) }
                     }
                 )
             }
@@ -94,12 +99,12 @@ class MainActivity : ComponentActivity() {
 
     override fun onResume() {
         super.onResume()
-        permissionsGranted.value = hasAllPermissions()
+        permissionsGranted.value = hasEssentialPermissions()
     }
 
-    private fun hasAllPermissions(): Boolean = requiredPermissions.all {
-        ContextCompat.checkSelfPermission(this, it) == PackageManager.PERMISSION_GRANTED
-    }
+    private fun hasEssentialPermissions(): Boolean = requiredPermissions
+        .filter { it != Manifest.permission.POST_NOTIFICATIONS }
+        .all { ContextCompat.checkSelfPermission(this, it) == PackageManager.PERMISSION_GRANTED }
 
     @Suppress("unused")
     private fun openAppSettings() {

app/src/main/kotlin/org/soulstone/vigil/data/TrackerRepository.kt

@@ -1,6 +1,8 @@
 package org.soulstone.vigil.data
 
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
 import org.soulstone.vigil.data.db.SightingEntity
 import org.soulstone.vigil.data.db.TrackerEntity
 import org.soulstone.vigil.data.db.VigilDatabase
@@ -18,15 +20,28 @@ import org.soulstone.vigil.util.Geohash
  */
 class TrackerRepository(private val db: VigilDatabase) {
 
+    // Serialises record() so the read-modify-write of a tracker row is atomic —
+    // concurrent observations were racing and losing count / first-seen updates.
+    private val mutex = Mutex()
+
     data class RecordResult(val tracker: TrackerEntity, val newlyAlerting: Boolean)
 
     fun observeTrackers(): Flow<List<TrackerEntity>> = db.trackerDao().observeAll()
 
-    suspend fun setApproved(id: String, approved: Boolean) =
+    // Under the same lock as record() so a concurrent observation can't clobber the
+    // user's choice back to its stale value.
+    suspend fun setApproved(id: String, approved: Boolean) = mutex.withLock {
         db.trackerDao().setApproved(id, approved)
+    }
+
+    suspend fun clearBaseline(id: String) = mutex.withLock {
+        db.trackerDao().clearBaseline(id)
+    }
 
     suspend fun prune(retentionDays: Int = RETENTION_DAYS) {
-        db.sightingDao().prune(System.currentTimeMillis() - retentionDays * BaselineManager.DAY_MS)
+        val cutoff = System.currentTimeMillis() - retentionDays * BaselineManager.DAY_MS
+        db.sightingDao().prune(cutoff)
+        db.trackerDao().pruneStale(cutoff)
     }
 
     /**
@@ -38,7 +53,7 @@ class TrackerRepository(private val db: VigilDatabase) {
         lat: Double?,
         lon: Double?,
         sensitivity: Sensitivity
-    ): RecordResult {
+    ): RecordResult = mutex.withLock {
         val now = obs.timestampMs
         val geohash7 = if (lat != null && lon != null) Geohash.encode(lat, lon, 7) else null
         val geohash6 = if (lat != null && lon != null) Geohash.encode(lat, lon, 6) else null
@@ -54,6 +69,15 @@ class TrackerRepository(private val db: VigilDatabase) {
         )
 
         val existing = db.trackerDao().get(obs.stableId)
+        val approved = existing?.approved ?: false
+
+        // Co-movement assessment first — it decides both display AND whether this
+        // tag is safe to baseline. Always computed (UI shows the evidence numbers).
+        val since = now - CoMovementEvaluator.WINDOW_MS
+        val recent = db.sightingDao().recentFor(obs.stableId, since)
+        val t = CoMovementEvaluator.thresholdsFor(sensitivity)
+        val assessment = CoMovementEvaluator.evaluate(recent, obs.ecosystem, t)
+        val coMoving = assessment.riskState != RiskState.OBSERVED
 
         // --- baseline: learn tags that live where you live -------------------
         var lastAnchorDay = existing?.lastAnchorDay ?: -1L
@@ -61,7 +85,10 @@ class TrackerRepository(private val db: VigilDatabase) {
         var baselineSafe = existing?.baselineSafe ?: false
         if (geohash6 != null) {
             val isAnchor = BaselineManager.noteLocation(db.placeDao(), geohash6, now)
-            if (isAnchor) {
+            // ONLY baseline-trust a tag that is NOT co-moving with you. A planted
+            // stalker tag co-moves (that's the whole detection), so it stays
+            // SUSPICIOUS/ALERTING and must never be auto-trusted into silence.
+            if (isAnchor && !coMoving) {
                 val day = now / BaselineManager.DAY_MS
                 if (day != lastAnchorDay) {
                     lastAnchorDay = day
@@ -70,19 +97,10 @@ class TrackerRepository(private val db: VigilDatabase) {
                 if (anchorDayCount >= BaselineManager.BASELINE_MIN_DAYS) baselineSafe = true
             }
         }
+        // Safety revoke: if a previously-trusted tag ever starts co-moving, drop trust.
+        if (baselineSafe && coMoving) baselineSafe = false
 
-        val approved = existing?.approved ?: false
-
-        // --- co-movement evaluation (skipped for trusted tags) ---------------
-        val riskState: RiskState
-        if (approved || baselineSafe) {
-            riskState = RiskState.OBSERVED
-        } else {
-            val since = now - CoMovementEvaluator.WINDOW_MS
-            val recent = db.sightingDao().recentFor(obs.stableId, since)
-            val t = CoMovementEvaluator.thresholdsFor(sensitivity)
-            riskState = CoMovementEvaluator.evaluate(recent, obs.ecosystem, t).riskState
-        }
+        val riskState = if (approved || baselineSafe) RiskState.OBSERVED else assessment.riskState
 
         val wasAlerting = existing?.riskState == RiskState.ALERTING.name
         val cooldownOk = now - (existing?.lastAlertMs ?: 0) > CoMovementEvaluator.ALERT_COOLDOWN_MS
@@ -100,10 +118,14 @@ class TrackerRepository(private val db: VigilDatabase) {
             baselineSafe = baselineSafe,
             lastAlertMs = if (newlyAlerting) now else (existing?.lastAlertMs ?: 0),
             lastAnchorDay = lastAnchorDay,
-            anchorDayCount = anchorDayCount
+            anchorDayCount = anchorDayCount,
+            lastRssi = obs.rssi,
+            peakRssi = maxOf(existing?.peakRssi ?: -127, obs.rssi),
+            distinctPlaces = assessment.distinctPlaces,
+            effectiveSightings = assessment.sightings
         )
         db.trackerDao().upsert(updated)
-        return RecordResult(updated, newlyAlerting)
+        RecordResult(updated, newlyAlerting)
     }
 
     companion object {

app/src/main/kotlin/org/soulstone/vigil/data/db/VigilDatabase.kt

@@ -32,7 +32,12 @@ data class TrackerEntity(
     val lastAlertMs: Long = 0,
     // baseline accounting: distinct calendar-days this tracker was seen at an anchor place
     val lastAnchorDay: Long = -1,
-    val anchorDayCount: Int = 0
+    val anchorDayCount: Int = 0,
+    // display / grounding: latest + peak RSSI and the current co-movement evidence
+    val lastRssi: Int = 0,
+    val peakRssi: Int = -127,
+    val distinctPlaces: Int = 0,
+    val effectiveSightings: Int = 0
 )
 
 /** One sighting of a tracker at one instant, geotagged when a fix is available. */
@@ -74,6 +79,16 @@ interface TrackerDao {
 
     @Query("UPDATE trackers SET approved = :approved WHERE stableId = :id")
     suspend fun setApproved(id: String, approved: Boolean)
+
+    // User says a baseline-trusted tag is "not mine" — drop trust and restart the
+    // day clock so it doesn't immediately re-trust.
+    @Query("UPDATE trackers SET baselineSafe = 0, anchorDayCount = 0, lastAnchorDay = -1 WHERE stableId = :id")
+    suspend fun clearBaseline(id: String)
+
+    // Rotated identities pile up (MAC rotation mints a new row each rotation); drop
+    // stale, non-approved rows so the table and the UI list don't grow without bound.
+    @Query("DELETE FROM trackers WHERE lastSeen < :cutoff AND approved = 0")
+    suspend fun pruneStale(cutoff: Long)
 }
 
 @Dao
@@ -99,7 +114,7 @@ interface PlaceDao {
 
 @Database(
     entities = [TrackerEntity::class, SightingEntity::class, PlaceEntity::class],
-    version = 1,
+    version = 2,
     exportSchema = false
 )
 abstract class VigilDatabase : RoomDatabase() {

app/src/main/kotlin/org/soulstone/vigil/detect/BaselineManager.kt

@@ -18,23 +18,29 @@ import org.soulstone.vigil.data.db.PlaceEntity
 object BaselineManager {
 
     const val DAY_MS = 86_400_000L
-    const val ANCHOR_MIN_VISITS = 60
+    const val DWELL_BUCKET_MS = 10 * 60_000L   // count at most one "visit" per 10-min dwell window
+    const val ANCHOR_MIN_VISITS = 18           // ~3h cumulative dwell before a cell counts as home/work
     const val BASELINE_MIN_DAYS = 3
 
-    /** Record a location fix in its cell; returns whether that cell is now an anchor. */
+    /**
+     * Note presence in a cell; returns whether it's an anchor. Crucially a cell
+     * accrues at most ONE visit per [DWELL_BUCKET_MS], so the anchor signal tracks
+     * time actually spent there — not how many trackers or adverts were seen.
+     *
+     * The previous per-sighting count was a real safety flaw: a busy street or a
+     * single chatty tracker could mint a fake "home" in seconds, which would then
+     * baseline-trust (silence alerts for) any tracker seen there — including a real
+     * stalking device.
+     */
     suspend fun noteLocation(placeDao: PlaceDao, geohash6: String, now: Long): Boolean {
-        val existing = placeDao.get(geohash6)
-        val visits = (existing?.visitCount ?: 0) + 1
+        val existing = placeDao.get(geohash6) ?: run {
+            placeDao.upsert(PlaceEntity(geohash6 = geohash6, visitCount = 1, lastSeen = now, anchor = false))
+            return false
+        }
+        if (now - existing.lastSeen < DWELL_BUCKET_MS) return existing.anchor
+        val visits = existing.visitCount + 1
         val anchor = visits >= ANCHOR_MIN_VISITS
-        placeDao.upsert(
-            PlaceEntity(
-                geohash6 = geohash6,
-                label = existing?.label ?: "",
-                visitCount = visits,
-                lastSeen = now,
-                anchor = anchor
-            )
-        )
+        placeDao.upsert(existing.copy(visitCount = visits, lastSeen = now, anchor = anchor))
         return anchor
     }
 }

app/src/main/kotlin/org/soulstone/vigil/detect/CoMovementEvaluator.kt

@@ -59,11 +59,14 @@ object CoMovementEvaluator {
         val sorted = sightings.sortedBy { it.timestamp }
 
         // Debounce: one effective sighting per DEDUP_MS so a chatty tag at 2s
-        // intervals doesn't trivially clear the count.
+        // intervals doesn't trivially clear the count. lastCounted is NULLABLE and
+        // always counts the first sighting — the old `Long.MIN_VALUE` seed overflowed
+        // (timestamp - Long.MIN_VALUE wraps negative), which pinned `effective` at 0
+        // and made the detector unable to EVER alert. (Caught by unit test.)
         var effective = 0
-        var lastCounted = Long.MIN_VALUE
+        var lastCounted: Long? = null
         for (s in sorted) {
-            if (s.timestamp - lastCounted >= DEDUP_MS) {
+            if (lastCounted == null || s.timestamp - lastCounted >= DEDUP_MS) {
                 effective++
                 lastCounted = s.timestamp
             }

app/src/main/kotlin/org/soulstone/vigil/detect/PresenceEngine.kt

@@ -137,8 +137,11 @@ class PresenceEngine {
         score += (cells.size.toDouble() / (2.0 * K_CELLS)).coerceIn(0.0, 1.0) * 20
         score += (if (coherent) 1.0 else 0.4) * 20
         val s = score.roundToInt()
+        // Coherence GATES the top tier: a crowd of many radios at many distances is
+        // incoherent (high RSSI variance), so it can reach PROBABLE at most, never
+        // CONFIRMED — this stops packed-transit false clone alarms.
         val tier = when {
-            s >= 85 -> Tier.CONFIRMED
+            s >= 85 && coherent -> Tier.CONFIRMED
             s >= 70 -> Tier.PROBABLE
             s >= 40 -> Tier.WATCHING
             else -> Tier.CLEAR

app/src/main/kotlin/org/soulstone/vigil/scan/BleTrackerScanner.kt

@@ -45,11 +45,22 @@ class BleTrackerScanner(
         .build()
 
     private val filters: List<ScanFilter> = buildList {
-        // Apple Find My — match presence of Apple manufacturer data.
-        add(ScanFilter.Builder().setManufacturerData(TrackerSignatures.APPLE_COMPANY_ID, ByteArray(0)).build())
-        // FMDN / Samsung / Tile / DULT — match their service UUIDs.
+        // Apple Find My — match ONLY the offline-finding message type (0x12), not
+        // every Apple device (iPhones/Watches/AirPods all advertise company 0x004C).
+        // Data+mask apply from the first manufacturer-data byte, which is the type.
+        add(
+            ScanFilter.Builder().setManufacturerData(
+                TrackerSignatures.APPLE_COMPANY_ID,
+                byteArrayOf(TrackerSignatures.APPLE_TYPE_FINDMY.toByte()),
+                byteArrayOf(0xFF.toByte())
+            ).build()
+        )
+        // FMDN / Samsung / Tile / DULT — match by SERVICE DATA presence, not the
+        // service-UUID list. These carry their payload in service data and may not
+        // advertise the plain UUID-list entry, so setServiceUuid can miss them
+        // entirely (AirGuard uses service-data presence filters for exactly this).
         for (uuid in TrackerSignatures.trackerServiceUuids) {
-            add(ScanFilter.Builder().setServiceUuid(uuid).build())
+            add(ScanFilter.Builder().setServiceData(uuid, ByteArray(0)).build())
         }
     }
 

app/src/main/kotlin/org/soulstone/vigil/scan/TrackerParser.kt

@@ -26,15 +26,16 @@ object TrackerParser {
 
         // --- Apple Find My (manufacturer data, company 0x004C) ---
         record.getManufacturerSpecificData(Sig.APPLE_COMPANY_ID)?.let { d ->
-            if (d.isNotEmpty() && (d[0].toInt() and 0xFF) == Sig.APPLE_TYPE_FINDMY) {
-                // Android strips the 2-byte company id, so d = [type(0x12),
-                // length(0x19), status, key(22), keyTopBits, hint]. The maintained
-                // bit lives in the status byte (index 2): set => near owner,
-                // cleared/absent => treat as separated.
-                val status = if (d.size > 2) d[2].toInt() and 0xFF else 0
+            // Require the FULL offline-finding frame. After Android strips the company
+            // id, d = [type, len, status, key(22), keyTopBits, hint] (~27 bytes). Short
+            // "nearby" frames carry no key — ignore them rather than fabricate a shared
+            // identity from the type/status bytes, which merged many distinct devices
+            // into one phantom "tracker" and misclassified it as separated.
+            if (d.size >= 25 && (d[0].toInt() and 0xFF) == Sig.APPLE_TYPE_FINDMY) {
+                val status = d[2].toInt() and 0xFF   // maintained bit set => near owner
                 val separated = if ((status and Sig.APPLE_STATUS_MAINTAINED_BIT) != 0)
                     SeparatedState.NEAR_OWNER else SeparatedState.SEPARATED
-                val keyBytes = if (d.size >= 25) d.copyOfRange(3, 25) else d
+                val keyBytes = d.copyOfRange(3, 25)
                 return TrackerObservation(
                     stableId = "apple:" + toHex(keyBytes),
                     ecosystem = TrackerEcosystem.APPLE_FIND_MY,

app/src/main/kotlin/org/soulstone/vigil/service/ScanService.kt

@@ -12,6 +12,7 @@ import android.os.VibrationEffect
 import android.os.Vibrator
 import android.os.VibratorManager
 import android.util.Log
+import java.util.concurrent.ConcurrentHashMap
 import androidx.core.app.NotificationCompat
 import androidx.lifecycle.LifecycleService
 import androidx.lifecycle.lifecycleScope
@@ -49,6 +50,10 @@ class ScanService : LifecycleService() {
         private const val NOTIFICATION_ID = 0x5161  // "VIGIL"
         private const val PRUNE_INTERVAL_MS = 6 * 3_600_000L
         private const val CLONE_COOLDOWN_MS = 2 * 3_600_000L
+        private const val MIN_RECORD_INTERVAL_MS = 15_000L  // per-device DB throttle
+        private const val ALERT_CHANNEL_ID = "vigil_alerts"
+        private const val ALERT_NOTIF_ID = 0x5162
+        private const val CLONE_NOTIF_ID = 0x5163
 
         const val ACTION_START = "org.soulstone.vigil.action.START"
         const val ACTION_STOP = "org.soulstone.vigil.action.STOP"
@@ -75,7 +80,8 @@ class ScanService : LifecycleService() {
     private lateinit var location: LocationProvider
     private lateinit var scanner: BleTrackerScanner
     private val presence = PresenceEngine()
-    private var lastCloneAlertMs = 0L
+    private val lastRecordedAt = ConcurrentHashMap<String, Long>()
+    @Volatile private var lastCloneAlertMs = 0L
     private var pruneJob: Job? = null
 
     override fun onCreate() {
@@ -109,8 +115,10 @@ class ScanService : LifecycleService() {
         pruneJob?.cancel()
         pruneJob = lifecycleScope.launch {
             while (true) {
-                delay(PRUNE_INTERVAL_MS)
+                // Prune first (frequent restarts previously meant the 6h-delayed
+                // prune rarely ran, so stale rotated identities accumulated).
                 runCatching { repo.prune() }.onFailure { Log.w(TAG, "prune failed: ${it.message}") }
+                delay(PRUNE_INTERVAL_MS)
             }
         }
     }
@@ -131,7 +139,16 @@ class ScanService : LifecycleService() {
             }
         }
 
-        // Temporal co-movement (identity path) — persisted + evaluated off-thread.
+        // Temporal co-movement (identity path). CALLBACK_TYPE_ALL_MATCHES fires on
+        // every advert (many/sec), so throttle the persisted path per device: the
+        // presence engine above still sees every advert, but the DB records at most
+        // one sighting per device per MIN_RECORD_INTERVAL_MS. Keeps the count
+        // meaningful and avoids hammering the database.
+        val last = lastRecordedAt[obs.stableId]
+        if (last != null && obs.timestampMs - last < MIN_RECORD_INTERVAL_MS) return
+        lastRecordedAt[obs.stableId] = obs.timestampMs
+        if (lastRecordedAt.size > 4096) lastRecordedAt.clear()  // guard vs MAC-rotation growth
+
         lifecycleScope.launch {
             val result = runCatching {
                 repo.record(obs, fix?.latitude, fix?.longitude, settings.sensitivity.value)
@@ -141,10 +158,13 @@ class ScanService : LifecycleService() {
     }
 
     private fun end() {
-        if (!_running.value) return
+        // No early-return guard: all stops below are idempotent, and begin() calls
+        // end() on a failed scanner start (when _running was never set) to make sure
+        // the location updates and foreground notification are released, not leaked.
         _running.value = false
         scanner.stop()
         location.stop()
+        lastRecordedAt.clear()
         pruneJob?.cancel(); pruneJob = null
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
             stopForeground(STOP_FOREGROUND_REMOVE)
@@ -177,9 +197,9 @@ class ScanService : LifecycleService() {
         val n = buildNotification(
             title = "Tracker following you",
             text = "${tracker.label} has been moving with you",
-            high = true
+            high = true, channelId = ALERT_CHANNEL_ID, ongoing = false
         )
-        getSystemService(NotificationManager::class.java)?.notify(NOTIFICATION_ID, n)
+        getSystemService(NotificationManager::class.java)?.notify(ALERT_NOTIF_ID, n)
         vibrate()
         Log.w(TAG, "ALERT: ${tracker.stableId} (${tracker.ecosystem})")
     }
@@ -188,9 +208,9 @@ class ScanService : LifecycleService() {
         val n = buildNotification(
             title = "Possible hidden tracker",
             text = "A rotating-ID tracker appears to be moving with you",
-            high = true
+            high = true, channelId = ALERT_CHANNEL_ID, ongoing = false
         )
-        getSystemService(NotificationManager::class.java)?.notify(NOTIFICATION_ID + 1, n)
+        getSystemService(NotificationManager::class.java)?.notify(CLONE_NOTIF_ID, n)
         vibrate()
         Log.w(TAG, "CLONE ALERT: rotating-id presence confirmed")
     }
@@ -208,7 +228,13 @@ class ScanService : LifecycleService() {
             @Suppress("DEPRECATION") getSystemService(Context.VIBRATOR_SERVICE) as? Vibrator
         }
 
-    private fun buildNotification(title: String, text: String, high: Boolean): Notification {
+    private fun buildNotification(
+        title: String,
+        text: String,
+        high: Boolean,
+        channelId: String = CHANNEL_ID,
+        ongoing: Boolean = true
+    ): Notification {
         val openIntent = Intent(this, MainActivity::class.java).apply {
             flags = Intent.FLAG_ACTIVITY_SINGLE_TOP or Intent.FLAG_ACTIVITY_CLEAR_TOP
         }
@@ -216,31 +242,48 @@ class ScanService : LifecycleService() {
             this, 0, openIntent,
             PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT
         )
-        return NotificationCompat.Builder(this, CHANNEL_ID)
+        return NotificationCompat.Builder(this, channelId)
             .setContentTitle(title)
             .setContentText(text)
             .setSmallIcon(android.R.drawable.ic_menu_view)
-            .setOngoing(true)
+            .setOngoing(ongoing)
+            .setAutoCancel(!ongoing)
             .setContentIntent(pi)
-            .setCategory(NotificationCompat.CATEGORY_SERVICE)
+            .setCategory(if (high) NotificationCompat.CATEGORY_ALARM else NotificationCompat.CATEGORY_SERVICE)
             .setPriority(if (high) NotificationCompat.PRIORITY_HIGH else NotificationCompat.PRIORITY_LOW)
-            .setOnlyAlertOnce(!high)
             .build()
     }
 
     private fun createNotificationChannel() {
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) return
         val mgr = getSystemService(NotificationManager::class.java) ?: return
-        if (mgr.getNotificationChannel(CHANNEL_ID) != null) return
-        mgr.createNotificationChannel(
-            NotificationChannel(
-                CHANNEL_ID,
-                getString(R.string.notification_channel_name),
-                NotificationManager.IMPORTANCE_LOW
-            ).apply {
-                description = getString(R.string.notification_channel_desc)
-                setShowBadge(false)
-            }
-        )
+        if (mgr.getNotificationChannel(CHANNEL_ID) == null) {
+            mgr.createNotificationChannel(
+                NotificationChannel(
+                    CHANNEL_ID,
+                    getString(R.string.notification_channel_name),
+                    NotificationManager.IMPORTANCE_LOW
+                ).apply {
+                    description = getString(R.string.notification_channel_desc)
+                    setShowBadge(false)
+                }
+            )
+        }
+        // Alerts get their OWN high-importance channel so a real "following you"
+        // warning actually makes noise + a heads-up banner. On Android 8+ channel
+        // importance overrides per-notification priority, so the ongoing LOW status
+        // channel could never sound an alert.
+        if (mgr.getNotificationChannel(ALERT_CHANNEL_ID) == null) {
+            mgr.createNotificationChannel(
+                NotificationChannel(
+                    ALERT_CHANNEL_ID,
+                    "Tracker alerts",
+                    NotificationManager.IMPORTANCE_HIGH
+                ).apply {
+                    description = "A tracker appears to be following you"
+                    enableVibration(true)
+                }
+            )
+        }
     }
 }

app/src/main/kotlin/org/soulstone/vigil/ui/MainScreen.kt

@@ -72,11 +72,15 @@ fun MainScreen(
     permissionMessage: String?,
     onStartStop: () -> Unit,
     onSetSensitivity: (Sensitivity) -> Unit,
-    onApprove: (String, Boolean) -> Unit
+    onApprove: (String, Boolean) -> Unit,
+    onDistrust: (String) -> Unit
 ) {
     var detail by remember { mutableStateOf<TrackerEntity?>(null) }
 
-    val active = trackers.filter { !isTrusted(it) }.sortedByDescending { riskRank(it) }
+    val now = System.currentTimeMillis()
+    val active = trackers
+        .filter { !isTrusted(it) && now - it.lastSeen < ACTIVE_WINDOW_MS }
+        .sortedByDescending { riskRank(it) }
     val trusted = trackers.filter { isTrusted(it) }
     val alerting = active.count { statusOf(it) == TrackerStatus.ALERTING }
     val suspicious = active.count { statusOf(it) == TrackerStatus.SUSPICIOUS }
@@ -159,14 +163,14 @@ fun MainScreen(
                 }
             } else {
                 items(active, key = { it.stableId }) { t ->
-                    TrackerCard(t, onClick = { detail = t }, onApprove = onApprove)
+                    TrackerCard(t, onClick = { detail = t }, onApprove = onApprove, onDistrust = onDistrust)
                 }
             }
 
             if (trusted.isNotEmpty()) {
                 item { SectionHeader("Trusted (${trusted.size})") }
                 items(trusted, key = { it.stableId }) { t ->
-                    TrackerCard(t, onClick = { detail = t }, onApprove = onApprove)
+                    TrackerCard(t, onClick = { detail = t }, onApprove = onApprove, onDistrust = onDistrust)
                 }
             }
 
@@ -188,7 +192,11 @@ fun MainScreen(
             sheetState = sheetState,
             containerColor = MaterialTheme.colorScheme.surface
         ) {
-            TrackerDetail(t, onApprove = { id, a -> onApprove(id, a); detail = null })
+            TrackerDetail(
+                t,
+                onApprove = { id, a -> onApprove(id, a); detail = null },
+                onDistrust = { id -> onDistrust(id); detail = null }
+            )
         }
     }
 }
@@ -283,7 +291,12 @@ private fun SectionHeader(text: String) {
 }
 
 @Composable
-private fun TrackerCard(t: TrackerEntity, onClick: () -> Unit, onApprove: (String, Boolean) -> Unit) {
+private fun TrackerCard(
+    t: TrackerEntity,
+    onClick: () -> Unit,
+    onApprove: (String, Boolean) -> Unit,
+    onDistrust: (String) -> Unit
+) {
     val status = statusOf(t)
     val accent = statusColor(status)
     Card(
@@ -302,7 +315,7 @@ private fun TrackerCard(t: TrackerEntity, onClick: () -> Unit, onApprove: (Strin
             Column(Modifier.weight(1f)) {
                 Text(ecosystemDisplay(t.ecosystem), fontWeight = FontWeight.SemiBold)
                 Text(
-                    "${statusLabel(status)} · ${t.sightingCount} sightings · ${relative(t.lastSeen)}",
+                    "${statusLabel(status)} · ${t.distinctPlaces} places · ${t.lastRssi} dBm · ${relative(t.lastSeen)}",
                     style = MaterialTheme.typography.bodySmall,
                     color = MaterialTheme.colorScheme.onSurfaceVariant
                 )
@@ -310,10 +323,8 @@ private fun TrackerCard(t: TrackerEntity, onClick: () -> Unit, onApprove: (Strin
             when (status) {
                 TrackerStatus.SAFE_APPROVED ->
                     TextButton(onClick = { onApprove(t.stableId, false) }) { Text("Undo") }
-                TrackerStatus.SAFE_BASELINE -> Icon(
-                    Icons.Filled.Verified, null,
-                    tint = VigilGreen, modifier = Modifier.size(20.dp)
-                )
+                TrackerStatus.SAFE_BASELINE ->
+                    TextButton(onClick = { onDistrust(t.stableId) }) { Text("Not mine") }
                 else -> TextButton(onClick = { onApprove(t.stableId, true) }) { Text("It's mine") }
             }
         }
@@ -321,7 +332,11 @@ private fun TrackerCard(t: TrackerEntity, onClick: () -> Unit, onApprove: (Strin
 }
 
 @Composable
-private fun TrackerDetail(t: TrackerEntity, onApprove: (String, Boolean) -> Unit) {
+private fun TrackerDetail(
+    t: TrackerEntity,
+    onApprove: (String, Boolean) -> Unit,
+    onDistrust: (String) -> Unit
+) {
     val status = statusOf(t)
     Column(Modifier.fillMaxWidth().padding(24.dp)) {
         Row(verticalAlignment = Alignment.CenterVertically) {
@@ -333,11 +348,14 @@ private fun TrackerDetail(t: TrackerEntity, onApprove: (String, Boolean) -> Unit
         Text(statusLabel(status), color = statusColor(status), fontWeight = FontWeight.SemiBold)
         Spacer(Modifier.height(16.dp))
 
-        DetailRow("Sightings", t.sightingCount.toString())
+        DetailRow("Signal (last / peak)", "${t.lastRssi} / ${t.peakRssi} dBm")
+        DetailRow("Distinct places", t.distinctPlaces.toString())
+        DetailRow("Co-movement sightings", t.effectiveSightings.toString())
+        DetailRow("Adverts logged", t.sightingCount.toString())
         DetailRow("First seen", relative(t.firstSeen))
         DetailRow("Last seen", relative(t.lastSeen))
         if (t.anchorDayCount > 0) {
-            DetailRow("Days seen at your places", "${t.anchorDayCount} (trusted at 3)")
+            DetailRow("Days at your places", "${t.anchorDayCount} / 3 to trust")
         }
         DetailRow("Identity", t.stableId.take(22) + "…")
 
@@ -348,14 +366,19 @@ private fun TrackerDetail(t: TrackerEntity, onApprove: (String, Boolean) -> Unit
             color = MaterialTheme.colorScheme.onSurfaceVariant
         )
         Spacer(Modifier.height(20.dp))
-        if (status == TrackerStatus.SAFE_APPROVED) {
-            Button(onClick = { onApprove(t.stableId, false) }, modifier = Modifier.fillMaxWidth()) {
-                Text("Remove from approved")
-            }
-        } else if (status != TrackerStatus.SAFE_BASELINE) {
-            Button(onClick = { onApprove(t.stableId, true) }, modifier = Modifier.fillMaxWidth()) {
-                Text("This is mine — stop alerting")
-            }
+        when (status) {
+            TrackerStatus.SAFE_APPROVED ->
+                Button(onClick = { onApprove(t.stableId, false) }, modifier = Modifier.fillMaxWidth()) {
+                    Text("Remove from approved")
+                }
+            TrackerStatus.SAFE_BASELINE ->
+                Button(onClick = { onDistrust(t.stableId) }, modifier = Modifier.fillMaxWidth()) {
+                    Text("Not mine — re-check this tracker")
+                }
+            else ->
+                Button(onClick = { onApprove(t.stableId, true) }, modifier = Modifier.fillMaxWidth()) {
+                    Text("This is mine — stop alerting")
+                }
         }
         Spacer(Modifier.height(24.dp))
     }
@@ -371,6 +394,8 @@ private fun DetailRow(label: String, value: String) {
 
 // ---- pure helpers ----------------------------------------------------------
 
+private const val ACTIVE_WINDOW_MS = 10 * 60_000L  // trackers not seen this recently drop off "Active"
+
 private fun isTrusted(t: TrackerEntity) = t.approved || t.baselineSafe
 
 private fun riskRank(t: TrackerEntity): Int = when (statusOf(t)) {

app/src/test/kotlin/org/soulstone/vigil/detect/CoMovementEvaluatorTest.kt

@@ -0,0 +1,77 @@
+package org.soulstone.vigil.detect
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.soulstone.vigil.data.db.SightingEntity
+import org.soulstone.vigil.model.RiskState
+import org.soulstone.vigil.model.Sensitivity
+import org.soulstone.vigil.model.TrackerEcosystem
+
+/** Locks the co-movement alert logic: dedup, the RSSI proximity gate, and the
+ *  distinct-places / separated-state thresholds. MEDIUM = 3 sightings / 3 places /
+ *  45 min / -85 dBm. */
+class CoMovementEvaluatorTest {
+
+    private val t = CoMovementEvaluator.thresholdsFor(Sensitivity.MEDIUM)
+
+    private fun s(tsMin: Long, rssi: Int, cell: String?, separated: Boolean) =
+        SightingEntity(trackerId = "x", timestamp = tsMin * 60_000L, rssi = rssi, separated = separated, geohash7 = cell)
+
+    @Test fun emptyIsObserved() {
+        val a = CoMovementEvaluator.evaluate(emptyList(), TrackerEcosystem.APPLE_FIND_MY, t)
+        assertEquals(RiskState.OBSERVED, a.riskState)
+        assertEquals(0, a.distinctPlaces)
+    }
+
+    @Test fun separatedCloseAcrossPlacesAlerts() {
+        val list = listOf(
+            s(0, -70, "u000001", true),
+            s(30, -68, "u000002", true),
+            s(60, -72, "u000003", true)
+        )
+        val a = CoMovementEvaluator.evaluate(list, TrackerEcosystem.APPLE_FIND_MY, t)
+        assertEquals(RiskState.ALERTING, a.riskState)
+        assertEquals(3, a.distinctPlaces)
+        assertEquals(3, a.sightings)
+    }
+
+    @Test fun farSignalIsGatedOut() {
+        val list = listOf(
+            s(0, -95, "u000001", true),
+            s(30, -96, "u000002", true),
+            s(60, -97, "u000003", true)
+        )
+        // Seen across 3 places over an hour, but never close -> the RSSI gate holds it back.
+        assertEquals(RiskState.OBSERVED, CoMovementEvaluator.evaluate(list, TrackerEcosystem.APPLE_FIND_MY, t).riskState)
+    }
+
+    @Test fun tooFewPlacesIsSuspiciousNotAlerting() {
+        val list = listOf(
+            s(0, -70, "u000001", true),
+            s(30, -70, "u000001", true),
+            s(60, -70, "u000002", true)
+        )
+        val a = CoMovementEvaluator.evaluate(list, TrackerEcosystem.APPLE_FIND_MY, t)
+        assertEquals(RiskState.SUSPICIOUS, a.riskState)
+        assertEquals(2, a.distinctPlaces)
+    }
+
+    @Test fun nearOwnerNeverEscalates() {
+        val list = listOf(
+            s(0, -70, "u000001", false),
+            s(30, -70, "u000002", false),
+            s(60, -70, "u000003", false)
+        )
+        assertEquals(RiskState.OBSERVED, CoMovementEvaluator.evaluate(list, TrackerEcosystem.APPLE_FIND_MY, t).riskState)
+    }
+
+    @Test fun tileHasNoSeparatedFlagButStillCounts() {
+        val list = listOf(
+            s(0, -70, "u000001", false),
+            s(30, -70, "u000002", false),
+            s(60, -70, "u000003", false)
+        )
+        // Tile emits no separated flag, so any Tile is a live candidate.
+        assertEquals(RiskState.ALERTING, CoMovementEvaluator.evaluate(list, TrackerEcosystem.TILE, t).riskState)
+    }
+}