The app is a quiz based on the popular PlayStation game Buzz. You can host a game on an iPhone and other iPhones can join the game. Meanwhile, host mirrors display over AirPlay device like AppleTV to big screen. On the screen the quiz displays current scoreboard, a question and 4 possible answers. On each iPhone device there are 4 buttons which match to the answers presented on the big screen. The user who has the fastest correct answer gets 10 points, next one 8 etc.
Read more about EL Hackathon - March 2014 edition