IntruderSelfie silently snaps a front-camera photo every time the screen is unlocked with a precise timestamp. Key points Runs as a lightweight foreground service after device boot – no need to keep the app open. Works offline – no internet, ads, or third-party libraries. Uses only the minimum Android permissions: Camera for photos, Foreground-Service to stay alive, Boot-Completed to start after reboot, and Storage to save images locally. Compatible with Android 8 → 14 (API 26-35). How it works Install, grant Camera & Notification permissions once. A persistent notification “Watching for unlocks…” appears; you can minimise the app. Each unlock triggers a silent photo saved to the app. Photos remain on-device only; no cloud, no data sharing. Privacy & Security No analytics, trackers, or background network traffic. Source code is publicly available for review.