• by Mark Walsh  @markfwal, July 19, 2012

The iPhone continues to claim top dollar when it comes to mobile advertising. The Apple smartphone commanded eCPMs of $2.85 in the second quarter, followed by Android at $2.10, according to Opera Software’s second-quarter mobile ad report. Microsoft’s Windows Phone platform had the lowest eCPM rate, at 20 cents.

Apple’s iOS operating system also dominated in overall market share on Opera’s mobile ad platform, serving 35 billion ad impressions a month globally. iOS accounted for 46% of traffic and 61% of ad revenue, with Android a distant second, at 24% of traffic, and 25% of revenue, respectively. Windows Phone had less than 1% share in both categories.

Not all ad platforms skew toward iOS as heavily as Opera.

Rather, they typically reflect Android's leading market share across devices. A separate study this week from mobile ad marketplace Adfonic -- drawing on thousands of mobile ad campaigns -- found Android increased its share of global ad impressions in the second quarter to 46%, while iOS’ share fell from 45% to 34%.

The Opera report also spotlighted the high average eCPM of $3.96 for the iPad. That means that even though the Apple tablet accounts for only about 7% of traffic on Opera’s network, it generates more than 14% of ad revenue.

“The iPad is also achieving significant user adoption in user groups that are highly desirable to advertisers,” it stated. “For example, 40% of physicians own or plan to own an iPad or tablet by the end of 2012, according to Nielsen projections.”

iOS delivers the majority of rich media impressions compared to Android. Regardless of platform, the format leads to higher engagement: 66% of users who click through to a video, for instance, will complete that interaction and spend 52 seconds watching video.

Opera also noted that adoption of HTML rich media ads has increased sharply in the first half of 2012 at the expense of standard ads. Rich media executions rose from 28% in January to 51% in June, while standard banners from 35% fell to 21% of ads. Expandable banners also fell from 31% to 15%. Video ads more than doubled to 13%. 

Among ad categories, business and finance generated the most revenue per impression.

“We see this trend continuing in the near term, while remaining optimistic about social networking as a revenue driver over the long term,” stated the report. Regionally, North America had the most ad requests, accounting for nearly three-quarters (73%) of the global total. The average U.S. eCPM was $1.98, a bit higher than the global average of $1.90.