Zynga Inc. is the world's largest social game developer with users playing their games which include CityVille, FarmVille, FrontierVille, Words With Friends, Mafia Wars, Zynga Poker, Cafe World, and Treasure Isle. Zynga Inc. games are available on a number of global platforms including Facebook, MySpace, Yahoo, the iPad, the iPhone and Android devices. They operate their games as live services, by which they mean that they continue to support and update games after launch and gather daily, metrics-based player feedback that enable them to continually enhance their games by adding new content and features. All of their games are free to play, and they generate revenue through the in-game sale of virtual goods and advertising.