The program costs $9.99 on the iTunes App Store. While the iPod Touch, the iPod Nano and the iPod Classic all support the Nike+ iPod pedometer, RunKeeper does them one step better by tapping into the native G.P.S. capability of the iPhone 3G. While a person is jogging, RunKeeper displays the current pace, distance and time as well as a bar graph of the speed over time. After the run, the program automatically uploads the data to www.runkeeper.com. Log in there to see a Google map of the route as well as the run’s total distance.

In a few tests, the iPhone’s G.P.S. chip had trouble finding the exact location but still recorded the speed and distance at the end of the run. The program works best in wide-open areas, as city coverage is a bit spotty. Additional tips and tweaks can be found on RunKeeper’s site, including advice on buying the right waterproof case for training with your phone, ensuring the phone doesn’t get as hot and sweaty as you do.