Adobe Flash Builder

Adobe Flash Builder (previously known as Adobe Flex Builder) is an integrated development environment (IDE) built on the Eclipse platform that speeds development of rich Internet applications (RIAs) and cross-platform desktop applications, particularly for the Adobe AIR platform. Adobe Flash Builder 4 is available in two editions: Standard and Premium.
Adobe Flash Builder offers built-in code editors for MXML and ActionScript and a WYSIWYG editor for modifying MXML applications. Adobe Flash Builder includes an interactive debugger, allowing developers to step through code execution while inspecting variables and watching expressions. Flex Builder 3 added support for performance analysis. The profiling view displays statistical information about memory use in addition to function call execution time.
Prior to version 4, this product was known as Flex Builder. The name change is meant to signify its connection to other products in the Adobe Flash Platform and to create a clear distinction between the open source free Flex SDK and the IDE.