I downloaded this app to test the speedo on my scooter and check top speed. Its neat how it puts a red dot on your top speed. I agree with other reviews though, battery usage is insane. Even when the app is closed and location is off for that program iPhone battery life goes down the toilet. I used it, then had to delete it because of excessive battery drain.
MJEVERYTHiNG about GPS Speed, v2.1