Problem with those apps is the minimum accuracy is 50m so the speed updating is slow. Not bad for checking the accuracy of your own speedo though if you can hold a particular speed for some distance.
Just playing with trapster at the moment which has a speedo function as well as the speed trap finding/reporting as well.
I'm using a Galaxy S1 by the way, GPS is ok, but accuracy is around the 25 - 50 metre mark. May be more accurate in other phones.
Thought for the day: Some people are like Slinkies - not really good for anything but they're funny when they're pushed down the stairs. Also: Who picks up guide dog shit?
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