Mobile and social game developer CrowdStar today announced that co-founder and general manager of products Jeffrey Tseng has been promoted to CEO of the company. Former CEO and co-founder Peter Relan returns to his post of executive chairman on CrowdStar’s board of directors.

CrowdStar said that the change comes as it completes its transformation to become a “100 percent mobile company.” Relan said that Tseng was instrumental in the company’s successful pivot to mobile social gaming.

“CrowdStar is fully committed to mobile,” Relan told us back in April. “We’re going to keep running our profitable PC Facebook games like Happy Aquarium, Happy Pets, Wasteland Empires and It Girl but our focus going forward will be purely mobile-based. We see tremendous potential in mobile as our target audience of females is very active there. We also have plans to create Facebook social-graph-based mobile web games as well that work across Facebook and mobile.” According to AppData CrowdStar’s most successful Facebook game Happy Aquarium currently has 222,133 daily active users.

Tseng will also join the mobile gaming company’s Board of Directors along with CrowdStar co-founder Suren Markosian and  senior vice president and group managing director of TW Investments at Time Warner Inc. Rachel Lam.