Android Jumps Past iPhone in Ad Clicks, But Symbian Is Still Tops

Android-based handset owners in the U.S. are now clicking on more mobile ads than those with iPhones, according to Smaato, a mobile ad measurement firm. During the month of May, Smaato measured a U.S. Click Through Rate (CTR) index of 118 on Android (s goog) vs. 111 on iPhone (s aapl) devices — a reversal from April, when the iPhone’s CTR was 125 as compared to Android’s 95.

The timing of this swap is rather serendipitous as Apple’s latest developer terms appear to block the use of Google’s mobile advertising platform as well as AdMob’s ad measurement service — which Google purchased in November — although Google is unlikely to accept Apple’s actions without a fight.

Meanwhile, Symbian phones still lead the pack when it comes to high CTRs, just as they did last month, which prompted my suggestion that developers consider targeting apps at the Symbian platform, even though iPhone and Android are considered the hot handsets these days. Smaato reinforces my suggestion:

“Symbian remains the leading OS in terms of click through rates worldwide, this month with almost three times the click through rate of iPhone. Putting this into perspective, we have to consider the sheer number of Symbian devices compared to Apple devices, but it should again also serve as further proof to advertisers that the iPhone is far from the be-all and end-all in mobile advertising.”

Indeed, the biggest ad generation threat to Symbian is neither the iPhone nor Android — the lowly feature phone is on pace to topple worldwide Symbian clickthrough rates as early as next month, with continual CTR gains in every month of 2010.

Related research on GigaOM Pro (sub req’d):