• by Steve Smith , Staff Writer @popeyesm, October 25, 2012

According to Opera, one of the largest mobile ad platforms in the world,  iOS -- and especially the app environment -- are the main drivers of revenue. In its Q3 2012 report on 40 billion monthly ad impressions served across over 10,000 mobile sites and apps, the company finds that iOS delivered the highest effective CPMs of any mobile platform, with eCPMs of $1.48 for iPhone and $4.42 for iPad. Android continues to underperform its rival, with an eCPM of $.88, below even the rapidly dwindling RIM platform ($1.06 eCPMs).

In overall mobile traffic share, iOS is still well ahead of competitors, holding 46.37% compared to next-best Android at 24.66%. Keeping in mind that Opera is only reporting on the publishers that sit on its ad platform (which include app-heavy major media like CBS, Pandora, theguardian, MLB and Shazam), the report sees 80.7% of total traffic coming from apps, generating 72.7% of all revenue. And while the mobile Web is only generating 19.3% of traffic on Opera’s platform, it is responsible for a disproportionate 27.3% of revenue.

While the business and finance segments have always delivered the most revenue per impression, the category’s overall share of the revenue on opera’s platform was exceeded by the sports category and also music/video/media. In fact the entertainment industry’s embrace of mobile advertising can be seen in the category’s nearly 20% share of all ad impressions -- exceeded only by social media, which is seeing continued inventory growth as the social nets optimize their mobile experiences.

Seventy percent of the ads Opera is serving are into the North American market, where U.S. eCPMs continue to lead the world ($1.37). But the EU average eCPM has now declined from parity with the global average (now at $1.31) to $1.13. Opera notes that the gap between U.S. ad rates and the rest of the world is increasing. Non-U.S./EU markets now have an eCPM of $.73, 44% lower than the global average, compared to the last quarter, when it was 17% lower.

Opera-Singer photo from Shutterstock