FOURSQUARE Incorporating gaming elements, this location-based social network allows users to â€œcheck inâ€ at various locations earning badges and rewards. This relatively new geolocation social network is rapidly growing in popularity and gained 1 million users after only a year, and 2 million users a few months later. (By comparison, it took Twitter two years to get to 1 million users.) Some companies have partnered up with Foursquare to offer special promotions and giveaways to contest winners. Users can win points and badges for checking in and ultimately become the â€œmayorâ€ of a venue. To leverage this, some small and large businesses offer specials to mayors.