Sencha will compete with others in the mobile application development space, such as and . Rhomobile's Rhodes framework and Appcelerator's Titanium framework both supports native development

The upcoming Ext JS 4 release, or Ext 4, features improvements in stability, speed, and flexibility. Ext JS is for development of desktop applications.

"Speed is very important to us and, with Ext 4, is one of our top priorities," said Spencer. Continual performance testing for code boosts framework speed. A new layout engine also assists with performance and flexibility. Also, unit tests offer 90 percent of code coverage, providing stability, Spencer said. He also cited documentation improvements. "With Ext 4, we have the best documentation we've ever created, and not by a short way -- by a long way."

Also featured are improvements for charting and disabled accessibility.

Ext JS 4 is set for a beta release in six weeks, with general availability due on February 28.