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Flex is a highly productive, free open source framework for building and maintaining expressive web applications that deploy consistently on all major browsers, desktops, and operating systems. While Flex applications can be built using only the free Flex SDK, developers can use Adobe® Flex® Builder™ 3 software to dramatically accelerate development. Try Flex Builder 3 free for 60 days.

Powerful coding tools
Flex Builder 3 is a powerful Eclipse based IDE that includes editors for MXML, ActionScript™, and CSS, as well as syntax coloring, statement completion, code Collapse, interactive step-through debugging, and more.

Rich visual layout (Enhanced in Flex Builder 3)
Visually design and preview user interface layout, appearance, and behavior using a rich library of built-in components. Extend the built-in components or create new ones as needed.

New in Flex Builder 3 ¡ª Interactively set and preview CSS values on any of your components in Flex Builder Design view. you can free download Adobe Flex Builder 3.0.2 now.
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