- In the US in 2008, iPhone accounted for 32% of mobile ads worldwide, 46% of mobile ad placements in US, more than other smartphone OSes combined
- There are around 1billion PCs worldwide (Forrester)There are around 4 billion mobile cellular subscribers (ITU/cellular-news) - note, doesn't mean they have Internet access.
- By 2012, the number of devices accessing the Internet will double to more than 3 billion, half of which will be mobile devices.(IDC)
- To many people in the world their "handheld device" *is* their computer and some countries see over 100% penetration (many mobile devices per person)
Hope these are helpful!