Foursquare is a mobile application that is a cross between a friend-finder, a social city-guide, and a game that rewards you for doing interesting things.
Foursquare lets you "check in" to a place when you're there, tell friends where you are, and track the history of where you've been--and who you've been there with. Foursquare challenges you to explore your city in new and fun ways by earning points, winning mayorships, and unlocking badges and specials for trying new places and revisiting old favorites.
Get foursquare on your mobile device! We have apps for the iPhone (and iPod touch), BlackBerry, Android, and third-party developers have made apps that support check ins for Windows Mobile, Palm Pre, Nokia Symbian, and the iPad. If you don't have one of these phones, you can always use our mobile website or if you prefer, check in via SMS.