Android phone users are downloading lots of apps. But app developers would be happier if those users would pay for them. To help make that happen, Scoreloop is adding the ability to make payments for Android apps to its suite of social gaming tools for Google’s Android operating system.

Scoreloop started on the iPhone, providing social features for iPhone games. But in a diversification move it is spreading to Android, which isn’t as mature as the iPhone. Google still hasn’t fixed payment problems on the Android Market, so developers have had to focus on making money from advertising on free apps, said Marc Gumpinger, chief executive of Scoreloop. The company already lets developers add ads to their games, and it is getting 100,000 new users per day on Android. But with this new method, developers can enable a secure payment system on their own. Users can buy virtual currency with real money to get virtual items in games.

The company, based in Munich, Germany, now provides every part of the equation for helping Android apps make money. It has its own discovery mechanisms for getting apps noticed through friend networks. And now it is adding PayPal and other ways to generate revenue from apps. Game developers no longer have to create their own merchant account to enable the secure payment system.

Hubert Sliwka, head of Gamesoul Studios, said PayPal is the best way to buy content inside games and that he is relieved Scoreloop is now taking care of everything.

Rivals include Aurora Feint and PapayaMobile. Scoreloop is getting more active on Android in part because Apple has made its own move to set up a social gaming network on the iPhone. But Scoreloop believes that Apple’s effort is complementary, as Apple is focused on the front-end interaction with consumers while Scoreloop focuses on the back-end infrastructure. Meanwhile, Google is leaving the territory wide open for companies like Scoreloop on Android.

Scoreloop says it has 200 million users of games that tap its software. The company was founded in 2008.