Mopub on Its $6.5 Million Round From Accel Partners

Mopub, which helps app developers optimize their ad inventory, said it raised $6.5 million in a round led by Accel Partners today. Accel’s Rich Wong joins the board and earlier investor Michael Dearing of Harrison Metal Capital will step down into more of an advisory role.

Sometimes dubbed the “DoubleClick of mobile,” Mopub helps developers optimize between different types of ad units like banners or interstitials or switch ads in and out from different ad networks. It also helps them manage between directly selling their inventory or serving ads that are brokered through networks.

After pulling its service out of beta in February, the company passed 1 billion monthly impressions last month and is working with about 250 publishers.

“We’ve been focused on scale and optimization,” said chief executive Jim Payne, who previously worked at AdMob, the mobile ad network Google agreed to acquire for $750 million in 2009. “Our optimizing capabilities can detect in real-time which ad networks are working best and automatically move traffic from one network to the another.”

He said direct sold advertising, or the kind where developers sell inventory directly to advertisers, is becoming more popular, especially as individual companies grow larger and become more recognized as everyday brands in their own right.

Accel already participated in the company’s seed round earlier this year. With them, Mopub gets a venture investor that’s also involved in one of the very biggest mobile gaming companies, Angry Birds-maker Rovio, and one that’s helped steer other companies into lucrative acquisitions like AdMob.

Payne said the costs of acquiring users has risen since Apple cracked down on the popular practice of buying downloads through offer walls.

“Incentivized downloads were much cheaper, like 5-10X cheaper than acquiring users through banner ads,” he said. “But we’ve essentially returned back to those older costs now.”

However, Apple hasn’t cracked down on developers cross-promoting their own apps, so many companies are still giving users virtual currency if they download others apps they produce. Mopub’s product can help with optimizing when and how to show these offers.