SensorFusion (demo)

Sensor Fusion as provided by Paul Lawitzki at thousand-thoughts.com but with some visual additions by me.
Fuse accelerometer, magnetometer and gyroscope into one sensor.
You will need a fast platform (1 GHz+, maybe even multi core) to get a good impression of what happens with azimuth, roll and pitch.
It will run on devices without gyroscope but the displayed values stay 0.

The source code can be downloaded from the above site or from my site.