RunKeeper is an iPhone app that uses the GPS feature to track your runs. So when you go out for a jog (presumably you’ll have your iPhone with you probably in an arm band), simply open up this application and hit Start. The app will time your run, and will geographically map your entire path. When you click "Stop", RunKeeper automatically sends your information to www.runkeeper.com, where you will see your entire run drawn out on Google maps. You’ll also get your total miles travelled, your MPH, and a graph that displays your speed trend.
Enough said, this app looks awesome. It’ll be $9.99 and it should be in the App Store very soon (it was already submitted).
Check out this demo video: