Google has not released sales predictions for devices based on its mobile operating system Android. But that doesn't stop Rich Miner, group manager for mobile platforms at the search giant, from being confident.

After his presentation on Thursday at the Emerging Communications Conference at the Computer History Museum in Silicon Valley, Miner said he expects Android-based devices to outpace sales of the popular iPhone.

"Once you have devices out there from Motorola, HTC, Samsung, and so on, there's a much larger potential market on Android than for the iPhone," Miner said. Despite the runaway success of the iPhone, which sold 4 million units in its first seven months of release, "there's a single manufacturer, it's targeted at a particular demographic, and it falls far short of the 1 billion mobile phones sold every year worldwide," added Miner.

Introduced last November, Android is a "complete open-source [software] stack" for mobile devices, not just an operating system," Miner said during his eComm presentation. Trying to stimulate application development for Android devices, Google is offering $10 million in prizes in its "Android Developers Challenge" for innovative and useful apps.

Opening the iPhone platform to third-party apps, Apple earlier this month released the software development kit for the popular consumer device. Apple said this week that the SDK has already been downloaded more than 100,000 times. Miner, however, pointed out that significant restrictions will still limit the creation of rich and useful applications for the iPhone.

"There are things I saw people doing with the first version of the Android SDK that it seems like you can't do with the iPhone at least at the moment," he says.

Google said last month at the 3GSM conference in Barcelona that the Android SDK has been downloaded 750,000 times. "That's for a device that doesn't even exist yet," remarked Miner.

Motorola, Samsung, HTC, and LG all belong to the Open Handset Alliance, which was formed last year by Google to promote open platforms and open networks in the mobile and wireless industry. All four are expected to release devices based on Android in the second half of this year. Miner indicated on Thursday that he expects one of the handset makers (most likely Taiwanese manufacturer HTC, according to industry reports) to reach the market before the other three.

Android and the iPhone, Miner adds, are aimed at different markets.

"It's not a competitive thing -- it's great that people are finally building tools so all of these third-party applications can be built and get out there," Miner said. "[If I were a developer] I'd certainly be looking at the iPhone, and if you believe there will be lots of Android phones out there, as we do, I'd be developing for both platforms."