You can buy the most stylish swim trunks in the store, but if you've got a beer belly, you'll probably want to do something about it. So before hitting the beach this summer, take out RunKeeper to lose those extra few pounds you gained over the year. You'll be better off for it. RunKeeper keeps track of how far and how long you've run, and you can control your music straight from the app. It will also log the history of your runs and personal records, so you can keep those speeds up and the calories down.