So common are the reports tracking US smartphone market share that any regular readers could probably recreate the most intimate rise and fall of each player without a second thought.

In Europe, however, the picture is typically more vague, although the numbers from InMobi's latest report suggest the continent's former king – Nokia – has been unseated by everyone's favourite upstart iPhone.

Apple acceleration

Based on InMobi's mobile ad data, iOS is now the dominant smartphone OS across Europe, accounting for just under 32 percent of the market. It's also the single largest ad device, fostering a 29.4 percent share.

Falling to second is Nokia, which has lost 6 percent of its market share in the last 90 days. The Finnish giant now holds a 19.7 percent share, with Android up 9.5 percent to a 12.9 percent share in response.

Indeed, four of the top 11 smartphone devices in Europe are Android – Motorola, Samsung, Htc and Google handsets combining for an 8.1 percent share of the market.

Changing times

"The rapid decline of Nokia is a major inflection point for the European mobile advertising community," said InMobi VP of global research and marketing James Lamberti.

"iPhone and Android devices trigger major increases in mobile internet consumption and drive rapid share gains against Nokia well beyond what shipments data would suggest."

The result of such growth is that the European market as a whole has grown by 88 percent in the last 90 days, iPhone ad impressions of 260 million and Android's ad impressions of 256 million the catalyst.

"The stage is set in Europe for the next level of mobile advertising industry growth with consumers now adopting powerful iPhone and Android devices at scale throughout the region," added InMobi VP and MD of Europe and the Middle East, Rob Jonas.

"It will be interesting to see how two radically different business models, Apple with its closed OS and device set versus Google with its open Android platform and multiple manufacturer approach, will compete in market."

The report can be downloaded in full over on InMobi's website.