This app has a menu item that initiates a compass calibration. It also gives you a compass, a direction movement indicator, a bubble level, your GPS coordinates, it bookmarks coordinates, and gives you a slew of raw data from the phone's sensors. Curiously, Google maps doesn't give you GPS coordinates, and I've always been concerned about getting injured while mountain biking and having to get my exact location.
The free app does all you need, but I went ahead and upgraded to the Pro version just to get rid of the ads. You can purchase the upgrade in-app.
GPS Status & Toolbox:
https://play.google.com/store/apps/deta ... gpsstatus2
