When Foursquare upgraded its mobile app last March at SXSW, it added some excellent new features which made the popular geo app even more compelling. Among these is a revamped leaderboard which shows how many points you've earned in the past 7 days compared to just your friends (I know I check in a lot more now in the hopes that I can one day beat Fred Wilson). The other one is a new Explore feature that gives you recommendations of nearby places to eat, drink, and shop based on where you are and your friends' past check-in behavior. Now these two features, along with the information users get after they check-in, are available to outside developers via Foursquare's API .