┬áCompass Calibration Nexus5 – GPS Essentials

1. Try to stay away from magnetic fields as far as you can

2. Open GPS Essentials and tap on compass (calibration will not work when the compass is not showing)

3. Put the phone on a flat surface with the display pointing up

4. Move the phone slowly, 5 seconds per full rotation is ok

5. Rotate the phone three full cycles around the axis pointing upward

6. Rotate the phone three full cycles around the axis pointing away from you

7. Rotate the phone three full cycles around the axis pointing right

8. The direction of rotation doesn’t matter

Here is a Youtube video to show you how it works.
There are other methods, like the 8-pattern, that are easier and might also calibrate the compass. Watch this Youtube video to find out how.