The basic concept for "Bloons" came from Stephen's wife. When Stephen asked her what would be fun in a new game, she talked about carnival games with darts and balloons. The first version of "Bloons" was developed quickly, and the game was released in April 2007. It proved popular, and soon reached nearly 100,000 players per day. By 2011, "Bloons" had been played over 3 billion times.