Here's how you can download the OpenSignal app free for Android devices.
1. Go to the Google Play page for the free app OpenSignal.
2. Tap the Install button.
OpenSignal lets you easily see cellular coverage, locate Wi-Fi hotspots, make your device's signal better, and improve your data speed. Plus you can use the signal compass to find the direction your signal is emanating fro, find local public networks, test your connection speed and a whole bunch of other cool stuff.