FaceAlert

FaceAlert 2.0

Free
It silently uses your camera to watch for someone standing over your shoulder.
 
2.0.17 (See all)

FaceAlert is a non-intrusive, background app that silently uses your camera to watch for someone standing over your shoulder. When someone appears behind you while working on your computer, FaceAlert displays the face of the person behind you in a notification window.

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