compasses and apps using android sensors

The image stability of android apps that use the sensors varies enourmously, many are very jiggly to the extent of being almost unusable.  It seems that the raw sensor data can be pretty noisy, and many apps make little or poor attempts to deal with this.  A few use heavy smoothing to try and fix this, but this increases the lag which doesn't help.

There are a few apps that seem to have tackled the problem successfully, so I shall have to find out how to do this to make my app work well.

1. Google's skymap is reasonably smooth, but noticeably laggy - could do a lot better 4/10
2. Sun Path sylde is very jiggly indeed - 2/10
3. 3D compass is quite responsive, but does tend to go a bit wild 5/10
4. Steady compass takes a few moments to settle when first started but then is then very steady indeed and has very little lag - just a shame it's only doing it in 2D.  8/10