While leviathans like Google and Apple battle for dominance of the mobile Web, Mobclix has adroitly maneuvered to build what is already a lucrative piece of the mobile-advertising landscape: a mobile-advertising exchange in which application developers can sell access to their audiences.

The roughly 30-person company based in Palo Alto, California, which launched publicly about a year and a half ago, is on a $25 million to $30 million run rate and serving some 3.5 billion ad impressions per month, mostly to the iPhone and iPod Touch.

"Every month, we're essentially doubling," said co-founder Krishna Subramanian. Mobclix is hiring eight people in engineering and business development, he said. It has 18 people in Palo Alto, five in San Francisco, and a fluctuating number in India.

Mobclix partners with some 6,000 application publishers and, at no cost to them, delivers to their users advertisements from 20-plus ad networks. Competitors include AdMob, which bought the AdWhirl mobile-ad aggregator last year, and Yahoo's Right Media, an online exchange. Mobclix makes its money by taking 10 to 20 percent from what ad networks get, typically 40 percent of the ad buy.

The company partners with both online and mobile networks, including Quattro Wireless, VideoEgg, JumpTap, Advertising.com, and Millennial Media.

Qayed Shareef, general manager of display at Traffic Market Place in El Segundo, California, said that his online network, one of the nation's largest, did not target mobile devices until signing up with Mobclix, and customers have adopted the option quickly.

Subramanian, previously co-founder of BlueLithium, an online ad network acquired by Yahoo for $300 million in 2007, said Mobclix started out in February 2008 to be a mobile-analytics firm but quickly shifted to become an advertising exchange when it became clear that was a tough way to make money.

Analytics capabilities are useful for targeting audiences based on demographics and behavior.

The company's four founders funded their efforts with $4.5 million from themselves, friends, family, and angel investors. Now that seems a good bet.

Apple's recent purchase of Quattro for $400 million and Google's ongoing attempt to buy AdMob for $750 million, which is pending a review by the U.S. Securities and Exchange Commission, convinced many advertisers that mobile is an important place to play, and test buys of $10,000 are turning into routine campaign purchases of $100,000, Subramanian said.

"A lot of people were worried how big the market was," he said. "Those questions are completely gone now."

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