Aurora Feint has enjoyed great success with its OpenFeint social game platform for the iPhone, allowing developers to socialize their games with leaderboards, achievements, and cross-game promotion. Now it is diversifying to Google’s Android platform.

That’s a big statement of validation for Android, and it’s a warning for Apple. Phones based on Google’s Android mobile operating system have been chasing the iPhone for some time, and now it looks like it makes good sense for Apple’s own iPhone ecosystem providers to start business on Android.

Aurora Feint rival Scoreloop has already adapted its social game platform for Android devices. Other rivals include PapayaMobile and Ngmoco.

The expansion to Android is possible due to a recent investment from China’s online game firm, The9, which has joined DeNA as an investor in Aurora Feint. Last week, Aurora Feint announced a new set of developers for its virtual goods platform for mobile devices.

Burlingame, Calif.-based Aurora Feint has more than 9,200 developers using its OpenFeint platform on the iOS operating system, which is used in the iPhone, iPod Touch and iPad. Those developers have created games with more than 28 million users. With OpenFeint-enabled games, developers get the benefits of a social layer, such as friends recommending games to each other or challenging each other in multiplayer duels. OpenFeint can help games spread in a viral fashion, increasing revenues for developers.

Starting this summer, Aurora Feint will offer its standard software development kit on Android , including a game discovery store, and mobile payment options. Game publishers such as Astraware, Digital Chocolate, Glu Mobile, Hudson Soft and independent studios like Distinct Dev (Moron Test), ustwo (Dot Dot Dot), Pik Pok (Flick Kick Football) and RocketCat Games (Hook Champ) are planning to launch Android apps with OpenFeint.

Aurora Feint says it continues to invest in its platform for the Apple iOS, where it is used in 2,200 games. But the attractions of expansion are clear: Android partners are shipping more than 160,000 Android devices per day.

“The explosion in mobile online gaming is a phenomenon that affects all members of the mobile ecosystem — from OS developers and OEMs to game developers and players,” said Peter Relan, executive chairman of Aurora Feint. “Online games are meant to be played with all of your friends — regardless of mobile operating system. We’ve decided to expand to Android with these mobile gaming giants because all smartphone owners deserve high quality, easy to find games.”

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