jQuery Mobile on a simple site

I am creating a mobile site and was thinking jQuery Mobile would be the right platform. However, in getting through the requirements it seems what's needed is CSS for styling - nothing extreme, HTML forms 开发者_开发技巧with some dynamic elements (i.e. select option 1 and some things change), and some AJAX for grabbing data.

Do I need jQuery Mobile to make sure a site with that simple of an architecture is uber-cross browser compatible? I'd like to hit iPhone 3 & 4, Blackberry, and Android. Don't have to worry about tablets or the like, this is strictly mobile phone. We'll show the desktop site to everyone else.

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jQuery Mobile is actually more about using mobile (mostly ios) type components, and gesture support. Yes, it helps to create a consistent cross-browser experience, but you don't need it to have your site show up correctly in various browsers. For that, you really just need to make sure all your code is valid, and that you're not using css (or other) hacks.