Compass with live value in 3D view of Accelerometer, Magnetic field meter, and Gyroscope meter.

The compass accuracy could be affected by the magnetic field near by...

To test your sensor accuracy, to find potential magnetic radiation near your house...

The measure in 3 ways:

1. current sensor in 3 axis

2. Maximum in 3 axis

3. total signal strength

Support from Android: 2.1
Best screen resolution: 480x800