Gree International wants to expand its already burgeoning mobile-gaming business with a $10 million third-party developer program and concentrate more on games than on platform development. "Not for all the third-party games, but some games, we're sending traffic from our first-party games. They're getting users from that direction. Instead of making a comprehensive platform, we're focusing on the cross-promotion among those top-grossing games. That's been effective," CEO Naoki Aoyagi says.