If your website looks the same on a smartphone as it does on a computer, you’ve got a problem.

The latest data from a study shows that almost 25% of the 35% of Americans who own smart phones, use their phone as their primary way of accessing the Internet:

the Pew Internet Project finds that one third of American adults – 35% – own smartphones. The Project’s May survey found that 83% of US adults have a cell phone of some kind, and that 42% of them own a smartphone. That translates into 35% of all adults.

Our definition of a smartphone owner includes anyone who falls into either of the following two categories: One-third of cell owners 33% say that their phone is a smartphone. Two in five cell owners 39% say that their phone operates on a smartphone platform these include iPhones and Blackberry devices, as well as phones running the Android, Windows or Palm operating systems.

Several demographic groups have high levels of smartphone adoption, including the financially well-off and well-educated, non-whites, and those under the age of 45.

Some 87% of smartphone owners access the internet or email on their handheld, including two-thirds 68% who do so on a typical day. When asked what device they normally use to access the internet, 25% of smartphone owners say that they mostly go online using their phone, rather than with a computer. While many of these individuals have other sources of online access at home, roughly one third of these “cell mostly” internet users lack a high-speed home broadband connection.

via Smartphone Adoption and Usage | Pew Research Center’s Internet & American Life Project.

The use of WordPress as a CMS (content management system) makes it easy to have your content display one way for a computer screen and a different way for a phone or tablet through the use of simple plugins.

• For tablets, OnSwipe is a solid solution that gives your site a magazine feel.
• For phones, WPTouch is a bit of a pain to configure but does the job.

There are also some themes that are purely built for mobile, but, that’s information for another post.