Global mobile advertising revenue nearly doubled in 2012, increasing from $4.9 billion to $9.1 billion. That's according to a study conducted by the Interactive Advertising Bureau and market intelligence group IHS. The report identifies the Asia/Pacific region as the largest mobile ad market in the world with revenue of $3.66 billion in 2012. At $3.63 billion, the North American market is just slightly smaller and Europe follows third with mobile ad spend of $1.54 billion.

The fact that mobile ad spending in Asia/Pacific exceeds the North American level appears surprising at first, but there is a simple explanation for it. The only reason for the high level of spending is the sheer size of the Asian market. Looking at ad spend per mobile subscriber delivers an entirely different result. It is in fact North America that is far ahead in mobile monetization. In 2012, average ad spend per mobile subscription in North America was $9.39, whereas it was only $1.32 in Asia/Pacific and $2.91 in Western Europe. Anyway, the numbers suggest that there is a lot of growth potential in mobile advertising.