One of the best workout apps in the App Store, RunKeeper, has been updated with a number of new features and improvements.

Probably the biggest addition are the new social features. Users can add friends directly from the app, compete against friends to reach the top of a personal leaderboard, and message friends that have slacked off exercising.

In the me tab, users can now compare current activity data and the recent past, view all of their personal records, and check progress against specified goals

Finally, users can also schedule workout reminders to keep on top of a fitness regimen.

Other improvements include an updated save workout screen, updated Facebook integration, and improved stability for heart rate tracking in iOS 6.

RunKeeper is designed for the iPhone/iPod touch and is compatible with the iPad. It is also optimized for the larger display of the iPhone 5. It can be downloaded in the App Store now.

Along with the large amount of features, the free price also makes the app a winner. RunKeeper once cost $9.99, but after an enormously successful month-long promotion in 2011, the developer decided to make the free price permanent.

If you want to shape up, feel free to take a look at our AppLists for Getting into Shape and Gym Companion Apps.