With the growing popularity of the iPhone and other mobile handsets, it will eventually become important for you to prepare your WordPress blog for being viewed on mobile devices.
Thanks to the flexibility of WordPress, there is now a WordPress plugin you can use called MobilePress, which will improve how your website is viewed in mobile web browsers.
MobilePress is a WordPress plugin that will render your WordPress blog on mobile handsets, with the ability to use customized themes. The plugin also allows specific themes for specific devices / mobile browsers, such as iPhone, Opera Mini, Windows CE Mobile and other generic handset browsers.
The plugin also allows WordPress theme developers to create custom mobile themes for WordPress blogs using the MobilePress plugin. Therefore, theme designers can create specific iPhone themes or generic themes.