jQuery Mobile is a Touch-Optimized Web Framework for Smartphones & Tablets. It is a unified user interface system across 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.

The aim is to provide tools to build dynamic touch interfaces that will adapt gracefully to a range of device form factors. The system will include both layouts (lists, detail panes, overlays) and a rich set of form controls and UI widgets (toggles, sliders, tabs). jQuery Mobile is now under development for late 2010.

Source: http://jquerymobile.com/