Ext JS features hundreds of high-performance UI widgets that are meticulously designed to fit the needs of the simplest as well as the most complex web applications. Ext JS templates and layout manager give you full control over your display irrespective of devices and screen sizes. An advanced charting package allows you to visualize large quantities of data.
Along with AngularJS, they are the two industry leading frameworks for Rich UI development. At Nearshore Portugal, we developed in both ExtJS and AngularJS.