There’s a lot of great frameworks out there to help you make great mobile web sites and apps. Whether or not to use a framework depends on what you’re trying to do with your mobile web project. Be mindful of the differences and advantages/disadvantages of each and find the right fit for your project.
A unified, HTML5-based user interface system for all popular mobile device platforms, built on the rock-solid jQuery and jQuery UI foundation. Its lightweight code is built with progressive enhancement, and has a flexible, easily themeable design.
Sencha Touch, a high-performance HTML5 mobile application framework, is the cornerstone of the Sencha HTML5 platform. Built for enabling world-class user experiences, Sencha Touch is the only framework that enables developers to build powerful apps that work on iOS, Android, BlackBerry, Windows Phone, and more.
Zepto/jQuery plugin for mobile web development on the iPhone, Android, iPod Touch, and other forward-thinking devices.
Topcoat is Adobe’s new open source CSS framework with UI components optimized for both desktop and mobile pages (and PhoneGap apps).