Your screen becomes a window into a 3D room. With head tracking on, lean left, right, up, down or closer and the room shifts as if it were really behind the glass.
Drag with the mouse (or a finger) to turn the room. This works together with head tracking: drag the room round, then lean or look the other way and the view follows. Double-click to straighten it again.
The camera picture stays on this device. Nothing is recorded or uploaded. Works best on a laptop or desktop webcam, sitting about an arm's length away, with your face lit from the front.