GPSTest

GPSTest is a free and open source tool that shows you tons of information about satellites within the reach of your Android smartphone in real time. One of the most interesting aspects of this app, without a doubt, is that it can help you troubleshoot a poor GPS signal.

From the app's options menu, you can change the type of satellite view, analyze your own GPS, or calculate the interval between your signal's positions, all on a simple and intuitive interface.