Appcelerator is an open source platform that provides everything you need to build rich web, mobile and desktop applications.

Appcelerator is a fully-integrated platform for building Rich Internet Applications (RIAs). It provides everything you need to build a rich and highly interactive web site or application.

Appcelerator is powered by several powerful capabilities:

Message Oriented Architecture
Web Expression Language
Widget Framework
Integrated Services Platform


Appcelerator also provides a number of other capabilities, including:

Localization Framework
Client-side Validation Framework
Form-specific features
Several common JS utilities (e.g., Date formatting, Cookie manipulation)
Tools for client-side debugging
Flexible programming models (declarative or Javascript)
Built-in support for popular server-side programming languages
Organizations from around the world have developed applications on the Appcelerator Platform. Please see some of the case studies that profile these organizations and their experience with Appcelerator.
Website: http://appcelerator.org/

Try Appcelerator: http://try.appcelerator.org/

Applications Developed with Appcelerator: http://appcelerator.org/demos