Sencha Touch comes with a powerful data package. Developers can easily request data from a wide variety of sources whether by Ajax, JSONp, or YQL, bind that data to specific visual components or templates, and then take that data offline with localStorage writers. By leveraging SASS technology, Sencha Touch theming system allows developers to easily change variables and completely alter the presentation of their app. Sencha Touch comes with a robust animation system, allowing easy, flexible animations between screens and views. Slide, pop, and fade animations are included with the library, each with a robust set of options to change attributes like direction and masking style.
Sencha Touch is an open source software and is released under a GNU GPL license v3. There is no commercial licensing at this time. May be later! For more information about Sencha Touch and to download the current public beta, visit the following link: http://www.sencha.com/products/touch/