It’s a clever mashup; when you run 3D Compass the application combines the view from the phone’s camera with information from the GPS chip to map your location, information from the compass to give your bearing, and information from the tilt sensors to properly oriented you in relation to the two. The result is that whatever you point your phone at you get a combination map and video feed with an augmented compass layered over it. It’s a great way to check your bearings without taking your eyes off where you’re headed.
