Per Gartner, By 2013, mobile phones will overtake PCs as the most common Web access device worldwide.

According to Gartner estimates:
The total number of PCs in use will reach 1.62 billion units in 2012, all of which are capable of Internet access, even if some are not connected. By 2012, the combined installed base of smartphones and browser-equipped enhanced phones will exceed 1.69 billion units. From 2012 onwards, this combined installed base will be greater than the installed base for PCs.Nevertheless, most users in 2012 will use a PC as their primary Web access device and their phone as a secondary access device. However, as use of smartphones spreads globally, they will overtake the PC as the most common primary device for Web access sometime in 2015. This shift means that many websites will need to be reformatted or rebuilt. Mobile device users typically make many fewer “clicks” on a website than PC users, and websites not optimized for smaller screen formats will risk reduced customer interaction and fewer transactions.

This market barrier will be of particularly concern to:
Organizations in geographies where the PC is not as prevalent. Organizations with consumer-facing websites. Informational portals used by educational institutions and the government sector. Online retailers, banks and financial service providers will be the most exposed to this risk.