Apple: How to Maximize Battery Life

In order to maximize battery life, it is recommended to lock your screen when it is not in use. You can lock your device by manually pressing the power button of your device. Or, check the Auto-Lock Setting (Settings > Display & Brightness). The screen will go dark but the Navionics® Boating app will keep running, recording a track and receiving GPS signal, depending on your Location permissions.

Normally, battery life depends on certain factors such as the model, usage, and manner of connection amongst other factors.

NOTE: An estimate of 2 hours of continuous operation can be expected, but not guaranteed.