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Following Eye is an app which consists of an 3D Eye that looks directly at your face and follows it. It gives you the feeling that you are constantly watched. In fact, it reminds you that you are watched. Wherever you go, it watches you. Tracks your face when you move it. The Eye disappears when it doesn't see you. It has a blue pupil. The app itself is open source. Requires front camera.

Uses android’s face detection and libgdx to render 3d eye model.