Mobile check-in location service Foursquare has hit 15 million users, which is triple the number of users they had during this same time last year. Half of their users are in the U.S. and the other 50% is international. Now that Gowalla has been acquired and will be rolled into Facebook, Foursquare will have even less competition.
Currently Foursquare and Facebook Places are the top 2 check-in location services. SCVNGR has 2 millionusers worldwide, Loopt has 5 million, and MyTown has 4.5 million. However Foursquare’s competitors have not broken down how many of their users are based in the U.S.