Foursquare is a social networking website and mobile app that allows users to check-in at various locations and earn points and badges. Launched in 2009, it has over 33 million users worldwide. Users can check-in to venues using the mobile app or website and share check-ins on social media. The app tracks mayorships of places and offers special discounts to users from brands. It integrates with social networks like Facebook and Twitter and has users in over 50 countries.