Nguyen wanted to make games for people like himself: busy, harried, always on the move. "I pictured how people play," he says, as he taps his iPhone and reaches his other hand in the air. "One hand holding the train strap." He'd make a game for them.
Nguyen understood the mantra of game design that Nolan Bushnell, creator of Pong and founder of Atari, described as "easy to learn and difficult to master." He modeled the game on one of the most masocore analog creations ever: paddleball. The toy was a simple design – just a wooden paddle with a string attached to a rubber ball. But players would be lucky to bounce the ball more than a few times in a row.