Sencha
Welcome to the Ext JS 4.2!
Ext JS 4.2 is a pure JavaScript application framework that works everywhere from IE6 to the latest Chrome. It enables you to create the best cross-platform applications using nothing but a browser, and has a phenomenal API.
What’s New
We have also been posting summaries of new features and changes to our blog.
Upgrading
Check out our upgrade guide to see what has changed.
Sencha also offers training courses and professional services for companies wishing to use Ext JS 4.