Calculate rotation angle in degree in Android?

Question

I would like to calculate the angle between a starting point and a position after rotation. In the example, 90 degree. The device is on a board and rotates clockwise. The device does not move, only the board rotates. How can I calculate the angle? The image demonstrates what I mean. The angle could be between 0 and 360 degree. If you have questions, please ask me.

Answer 1

Not sure but you should take a look at this page : http://developer.android.com/reference/android/hardware/SensorEvent.html#values

There is a bunch of sensors and I think the gyroscope could do the trick.