If your thinking about upgrading to a windows mobile phone it is possible to use with just wifi. Using internet explorer would work as well as emails, aim, and any youtube cabs. I have 2 windows mobile phones from tmobile the dash and the wing and they are both great phones. Programs for windows mobile are endless which is why i like them. The os is great for wm both of my phones came with 6.0 but you can easily upgrade them to 6.1. A sight i found very helpful for information and programs would be
www.xda-developers.com they would be able to answer any question you might have.