Speed is free today on Amazon's Appstore for Android.
This will not be a long review.
Speed is a speedometer. Don't know what that is? Okay. A speedometer tells you have fast you are traveling. Speed will register speeds of 3 miles per hour or faster. I would never recommend using an app exactly like this when doing any of the following: biking, driving a car or boat, standing atop a train shooting at mercenaries while avoiding missiles from an enemy helicopter, or while on a treadmill or stationary bike. All but the last two are simply for safety reasons.
In response to one of the numb-nut reviewers I've added treadmill and stationary bike because this app does not work unless you are traveling across the face of the planet. It uses your GPS signal to do all the work. And it is displayed nicely with a leather seat background.
Speed -
