Prior acquisitions also include mobile game developer NewToy and Texas-based Bonfire Studios.

FORBES: Another Day, Another Zynga Acquisition

Interestingly, in October, the company also purchased a Texas-based mobile developer, Bonfire Studios, whose founders also worked on Age of Empires and Halo Wars.

FORBES: Zynga Ups Its Mobile Game With Purchase Of Startup Newtoy

EA, for instance, just bought the Chillingo, the publisher of the popular iPhone game Angry Birds, last week. (Though the purchase did not include rights to the game, which belong to its developer Rovio.) And Zynga bought iPhone developer Bonfire Studios, earlier this month.

FORBES: Zynga Vs. Electronic Arts: Both Are 'Social' Competitors, But Who Has The Better IP?