Want to take CitiBike but hate that their app won't give you directions door to door, use CitiBikeFinder
Screenshot-based deployment diff detection (with zero setup)
Send a microdonation to any cause with just a retweet
Visualize your mind
Feedback app for children
An app that cheers you up if the weather is bringing you down.
Facial recognition engine for Google Glass
Competitive sudoku: it's more than just a one-player game