How to add continuous movement to iPad app
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I'm writing a 3d car designer ipad app and I want to add a little "life" to it.  I want it to be similar to what "3D Car Builder" iPad app does, in that from the moment the app starts, there's just the slightest amount of "movement" in the scene.  Even if the iPad is sitting on the table, there's movement going on.

I'm testing on a 1st gen iPad, so whatever they've implemented, works on my device.  I have (iOS 5 installed). I've looked up several things, thinking this was developed with the accelerometer, or possibly magnetometer, core motion of some sort...I can't figure out where to start.  It might something as simple as moving the 3D scene in the x direction for a small amount, then y-direction, the negative x, then negative y.  I dunno, it's something simple.

Anyone know how I/they might have implemented this?
