Plugin-free Charting
No plugins, no problem. Ext JS 4 delivers the most advanced charting and graphing capabilities of any JavaScript framework, without relying on plugins, delivering pixel perfect visuals on any browser on any operating system. Leveraging SVG and VML, the Ext JS 4 charting package lets developers design and program their graphs once for all browsers.
Modern App Framework
Ext JS 4 is a major step forward for web frameworks. Building on Ext JS 3.3, our latest release adds over 350 new APIs, 50 new classes, and 65% more documentation. An entirely new data package equips developers to leverage features like Infinite Grid Scrolling to build an entirely new level of interactivity to web apps.
MVC Application Architecture
Ext JS 4 brings a whole new way to build client applications, by introducing the popular model-view-controller pattern to Ext JS. By allowing the separation of data management, logic and interface elements, Ext JS 4 makes it easier for even large development teams to work independently without worrying about stepping on each other's toes. Ext JS 4 ships with a helpful MVC guide to get started.

Charting
Drawing
Data Package
Enhanced Grid
Infinite Scrolling
Row Editor
Split DOM
Powerful Theming
New Class System
Layouts
Forms
Sandboxing
Compat.js
Documentation
Encapsulated Architecture
Component Query
Focus Manager
Z-Index Manager