Foursquare

Foursquare
Foursquare is a local search-and-discovery service mobile app which provides search results for its users. The app provides personalized recommendations of places to go to near a user's current location based on users' «previous browsing history, purchases, or check-in history».

The service was created in late 2008 and launched in 2009 by Dennis Crowley and Naveen Selvadurai. Crowley had previously founded the similar project Dodgeball as his graduate thesis project in the Interactive Telecommunications Program (ITP) at New York University. Google bought Dodgeball in 2005 and shut it down in 2009, replacing it with Google Latitude. Dodgeball user interactions were based on SMS technology, rather than an application. Foursquare was the second iteration of that same idea, that people can use mobile devices to interact with their environment. Foursquare was Dodgeball reimagined to take advantage of the new smartphones, like the iPhone, which had built in GPS to better detect a user's location.
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