One month after InMobi's figures for its own advertising network saw Android surge past iOS on a worldwide basis, the firm's latest stats sweep show a distinct drop off in acceleration for Google's platform in North America, with the momentum swinging back in Apple's favour.
In total, InMobi currently serves 35 billion monthly mobile advertising impressions to over 314 million consumers.
Android or Apple
InMobi puts iPhone's surge in North America across April down to the success of Verizon's iPhone 4.
Though Android has a 36.9 percent share of total InMobi impressions across the region 4 percentage points ahead of iOS Apple saw its own share leap by 9.4 percent from January, bringing the two platforms closer together at the top.
A similar boost in the following period would see iOS overtake Android by August, though the lack of any new iPhone hardware on the horizon makes that unlikely.
However, InMobi itself is keen to play up the role of smartphones as a whole within the field of mobile advertising.
"With smartphones now representing over 80 percent of all mobile ads in North America, advertisers and publishers are now focusing on providing consumers with engaging, rich ad experiences, it's crucial that the industry identifies, creates and tests the best creative executions to fully engage consumers," said VP managing director of North America, Anne Frisbie.
Worldwide war
Things are vastly different on a worldwide basis.
Combined, Nokia and Symbian have control of just shy of 38 percent of all ad impressions down from the 40 percent share highlighted in InMobi's last report, but still comfortably ahead of Android on 16.8 percent in second spot.
However, Nokia's dominance remains a hangover from an age on the way out, attests InMobi. It's only a matter of time before it is superseded at the top.
Changing game
Indeed, advertising on mobile as a whole is a changing business.
"With a large global contingent of mobile app developers for iOS, Android and now Windows Phone 7, these developers represent an invaluable part of the mobile ecosystem," added James Lamberti, VP of global research & marketing at the firm.
"Developers are among the most influential individuals in the future of the mobile market and their products will shape the future of mobile advertising.
"The landscape will be very interesting to watch over the next year as many developers began to focus on mobile web apps to help alleviate device and platform fragmentation issues."
Globally, InMobi claims 39 percent of all mobile ad impressions now occur on smartphones.
