SAN FRANCISCO -- Zynga will add more ways for people to play its Web games as it grooms its business for an initial public offering of stock that is aiming to raise $1 billion.
The expansion announced Tuesday served as part product announcement, part coming out party for Zynga.
Since it launched four years ago with a version of "Texas Hold 'Em Poker," Zynga has created entertaining diversions for 232 million players worldwide, largely on Facebook and other social networking services.
Those games also have become an annoyance for millions of other people subjected to their online friends' pleas for help in building virtual cities and farms.
In a step toward becoming more compelling to its users and less intrusive to outsiders, Zynga is working on its own online playground.
That service, currently called "Project Z," means Zynga's users won't have to flock to social networks to play games such as "CityVille," "FarmVille" and "Mafia Wars."
Several new titles will be added to the game line-up, including "CastleVille," "Dream Zoo" and "Bingo." Zynga is inserting the bingo game in a new online casino that will become the home for its poker games too.
Zynga didn't set a target date for when its own game-playing destination will be available. The company, based in San Francisco, also didn't say whether it believes the alternative site will lessen its dependence on Facebook, the main place where Zynga's games are currently played.
The appetite for Zynga's IPO has been fed by its connections to Facebook and the online hangout's 800 million users. Project Z still will draw upon Facebook's massive audience, because Zynga's website will still require a Facebook account to log on.
Zynga also is will offer three games that can be played on iPad software that Facebook began distributing Monday.
But Zynga didn't say whether Project Z will serve as a way to avoid sharing as much of its revenue with Facebook.
Zynga games are free, but the company charges for virtual items that can speed up or improve play. Facebook charges a 30 percent commission when Zynga users buy such items while playing on Facebook's website.
It is doubtful that Zynga founder and CEO Mark Pincus would do anything to jeopardize Zynga's relationship with Facebook, given the stakes riding on its IPO.
Zynga's fortunes ride on Facebook, as its own IPO documents make clear. "We generate substantially all of our revenue and players through the Facebook platform and expect to continue to do so for the foreseeable future," Zynga said in its papers, which were filed more than three months ago.