HopStop was an online city transit guide offering detailed, door-to-door biking, bus, subway, taxi, train, and walking directions in real time, as well as official transit maps for 600 cities around the world via Hopstop.com or apps for Android devices, iPads, iPhones, and Windows Phones. The company, founded in 2005, was named one of the top 100 fastest growing software companies in the United States in 2011.