Foursquare Labs Inc., commonly known as Foursquare, is a geolocation technology company and data cloud platform based in the United States. Founded by Dennis Crowley and Naveen Selvadurai in 2009, the company rose to prominence with the launch of its local search-and-discovery mobile app. The app, Foursquare City Guide, popularized the concept of real-time location sharing and checking-in.

Dennis Crowley is an American Internet entrepreneur who co-founded the social networking sites Dodgeball and Foursquare.