• by Mark Walsh  @markfwal, April 23, 2014

Google's Android for the first time has eclipsed iOS in mobile ad traffic globally, according to a quarterly report from mobile ad network Opera Mediaworks. Android accounted for 42.8% of ad impressions in the first quarter versus 38.2% for iOS. (Android smartphones surpassed iOS in the fourth quarter, but did not move ahead in overall mobile (smartphones + tablets) impressions until this year.

That suggests Android devices, including the Samsung’s Galaxy phones and other newer models, are attracting a comparable user base to that for the iPhone, Opera Mediaworks CEO Mahi de Silva toldForbes. And that, in turn, is leading to higher-quality ads shown on Android screens.

That said, Apple devices are still well ahead in generating revenue from ads. The iPhone and iPad drove 52.3% of sales compared to Android's 33.5%. But the latter figure is up from 26.7% a year, while iOS's share has slipped from 60%.

In a similar vein, a report from app analytics firm App Annie last week showed Android devices had more downloads while iOS was far higher in generating revenue. The Google PlayStore led the iOS App Store in downloads by 45% in the first quarter, up from 35% in the previous quarter. The App Store maintained a comfortable advantage in revenue, leading Google Play by 85%.

But the latter continued to narrow the revenue gap since the third quarter, when the App Store delivered more than twice the revenue of its Android-based counterpart. While emerging markets have helped to drive Android's download growth, mature markets like the U.S. and the U.K. are boosting Google Play revenue.

China was a big driver for App Store gains, with app revenue in China up 70% from the prior quarter.  Apple in January completed its deal to bring the iPhone to China Mobile, the nation's largest carrier with 700 million subscribers. That move reportedly led to a million new iPhone users in China in February.

The global war between Android and iOS goes on.