Casual games firm PlayFirst has announced that its CEO and founder John Welch is leaving the company to pursue other opportunities.

He's already been replaced by Mari Baker, who joins following previous senior executive roles at Navigenics, BabyCenter and Intuit.

She joins at an important time for PlayFirst, which is striving to take advantage of the opportunities presented by iPhone, and has already ported its Diner Dash game to Apple's platform.

In an interview with PocketGamer.biz last September, Welch said that iPhone was "the first mobile device popular and powerful enough" to make the most of PlayFirst's games.

However, the company is also an active licensor in the regular mobile space, working with companies like Glu Mobile and Gosub 60.

In related news, PlayFirst has also announced that Jim Wandrey is its new CFO, replacing Mike Dickey.