Pandora is hoping to turn its massive popularity on the iPhone into an ad sales windfall with the launch of new ad platform for the device.

Pandora's personalized streaming radio service is one of the more popular music applications available via the iPhone App Store, with more than 1.1 million downloads since launch. The new ad network, at launch, employs a sponsorship model, displaying a "brought to you by" style ad each time the Pandora application is launched.

The first two advertisers on board are Best Buy and Becks beer. Best Buy has the exclusive for the first thirty days, with Becks to follow.