Offerpal Media announced today that its “managed offer platform” is now available for iPhone app developers who are interested in monetizing their apps through offers.

Currently, most iPhone app and game developers monetize by either charging for the app or using an ad network.  By contrast, with offers, developers can allow their users to earn virtual currency or progress in the game by participating in targeted CPA advertisements like signing up for free trial subscriptions or taking surveys.

Offerpal has been doing this on social networks and gaming sites for a long time with apps like Friends For Sale on Facebook and virtual worlds like WeeWorld. Offers have proven to be a very effective way for social game developers to monetize on social networks: Offerpal says its network-wide average rate is $75 per day per 1,000 active users with eCPMs often above $150. The company says early tests on the iPhone are showing similar early metrics.

“We view the iPhone as the next big application platform,” said Anu Shukla, CEO of Offerpal. “At last count there were more than 10,000 iPhone applications, most of which are free or extremely low cost to use and have yet to provide developers with any significant revenues.”

Offerpal is looking for developers to help them beta test the program over the next several weeks. No documentation is publicly available yet on the integration process.

(Note: Offerpal is an advertiser on this blog.)