Baba joined KLab in 2003 and briefly worked at GREE starting in 2007. However, even while working full-time at start-up companies, he had been developing mobile game applications and websites as a side Business since his university days.
He founded Colopl in 2008 as a developer and owns 59% of the company. Colopl has five of the largest-grossing apps for Android smartphones, including Professional Baseball PRIDE, Treasure Trove Detective and Dino Dominion.
According to Forbes, he had an estimated net worth of $1.9 billion as of December 2014.