In order for NerdNav to work as a navigator it needs to know two things, your location and the direction that the device is pointing. Location is easy. As long as you give the device permission it gets your location very quickly. Direction, or heading, is more tricky and we need to give it some help.
Mobile devices use an internal magnetometer to determine heading and as the name suggests, this makes use of the Earth’s magnetic field. Quite often you will find that on starting the app, the device is still unsure of its heading, or it will think it is pointing in a different direction to reality.
The situation is particularly tricky if there are other magnetic devices nearby, e.g. hard drives in laptops.
To calibrate the heading and get accurate results simply take your mobile device and twist it around a few times. For example, just hold it in your hand and rotate your wrist. This allows your mobile device to detect differences in magnetic fields and then the magnetometer should start giving accurate heading results.