Compass

Navigational Compass for Android devices that utilise calibrated hardware sensors.

Note: This app can also be used to check if you have hardware sensors and, if so, the accuracy of your sensors (if you already know which way is North.)

Keep in mind that the sensors in your phone may be affected by various objects - metals, phone covers, etc., etc.
So remember to use this app as an approximation only.

Also worth noting: Some devices constantly need their sensors calibrated. Calibration may be achieved by opening this Compass app, or any other Compass type app, then turning your phone over a few times left to right, right to left, front to back, and back to front.

Enjoy!