<b>N.B</b> The app no longer requires Google Maps to install but the app will crash if you try to access the maps without having it. <b>N.B</b> It isn't possible to view your position on a map because Google Maps is the only map source and the API keys are not in the source code. If you need to use Google Maps install the developer's build from the website. Keep your eyes on the road, not your phone! Speed of Sound automatically adjusts your music player's volume while you're driving about with your GPS, lowering the volume while driving slowly or at a stoplight, and cranking it up on the highway. This is a feature available in some more expensive cars and sound systems. We're giving it to you for free to use on your phone. Just start up your music player, plug your phone into your car stereo, and open Speed of Sound.