AT&T Offers HTML5 SDK For Third-Party Mobile Web App Developers
January 11, 2012—AT&T’s HTML5 SDK is built around Sencha Touch and Ext JS. Sencha Touch is a powerful user interface framework developed by Sencha Labs that is used for building touchscreen-friendly mobile Web applications. One of the strengths of Sencha Touch is that it offers a standard widget set that allows developers to create mobile Web experiences that feel like native applications.
Ars Technica