Mozilla Stumbler is basically a tool that scans wireless networks to collect GPS information for its parent company’s Mozilla Location Service, which is a location database. This open-sourced network scanner stumbles upon new cell towers and Wi-Fi networks as you move spots. If your device’s battery is low or you aren’t moving, the app would stop or pause automatically. The app works when you walk, bike, or drive new routes. If you are just getting started with the app, begin with major intersections and streets before exploring smaller streets.