Android opened up a sizeable lead over the iPhone on the InMobi ad network in the third quarter in the U.S., with a 40.3% share of impressions compared to 20.8% for the Apple device. In the second quarter, Android had only a 4-point share advantage -- 33.5% to 29.6%.
But InMobi expects Apple to regain ground in the U.S. in the fourth quarter with the launch of the iPhone 4S and iOS 5 -- the latest version of its mobile operating system. The iPhone 4S sold a record-breaking 4 million units in its opening weekend. When it comes to individual handsets, the iPhone 4 remains the top device in North America with a 5.2% share, followed by the BlackBerry Torch 9800 and BlackBerry Curve 8520, each with 4.2%.
Overall, InMobi said North America mobile impressions jumped 50% in the quarter, adding up to nearly 27 billion for the region. That total is up from about 2 billion when InMobi entered the U.S. market last year after establishing footprints in Asia, Africa and Europe.