I\'m working on a mobile phone web app and I have several text fields that could benefit from . iPhones will adjust the keyboard for
Yes, any unsupported type will revert to the 'type=text' format.
I found a good page which lists out all the existing input types. I tried looking at it from different browsers, a bit interesting. Don't know if it will help you or not.
http://miketaylr.com/pres/html5/forms2.html
Browsers will fall back to type="text" when they encounter unsupported input type. So I think it's OK to use type="tel".
Short answer: yes. As @el.pescado mentions, browsers fall back to type=text
when they don't undertand the type. For more info about the other cool features you get from HTML5 forms, check out A Form of Madness, which is the forms chapter in Dive Into HTML5.