RWR: onlooker alert

RWR watches through the front camera for people looking at your screen from behind (shoulder surfers). When it sees one, it:

pops up a card over whatever app you are using with a snapshot of the onlooker (boxed in red, with "laser eyes" showing where they look),

posts a notification,

saves a photo or a short video clip (for example 10 s before to 10 s after) to your gallery, and optionally to your own Immich server.

It runs in the background and can be switched on and off from the Quick Settings panel.

Detection

Head tracking : a face turned toward the screen counts as looking. Lightest on battery.

Eye tracking : follows the irises and combines them with head pose, so it alerts only when the eyes point at the screen.

Your own face is recognised and ignored, and faces too far away to read the screen don't count.

A debug view shows live what the detector sees and why each face counts or not.

Private by design

Detection runs on the phone , offline, with bundled open-source models (YuNet and MediaPipe Face Landmarker). No analytics, no ads, no accounts.

Nothing leaves the phone unless you pair it with your own RWR server (Docker, open source, in the same repository). Then frames go only to your server, over TLS: detection runs there at full frame rate without draining your battery, and snapshots can be uploaded to Immich.

The camera is always off while the screen is off. Android shows its camera indicator while RWR is watching.

Requires Android 10 or newer and a front camera. The pop-up needs the "Display over other apps" permission.