History

2002|Macromedia coins the term Rich Internet Application (RIA) and after a few precursors begins development on a project codenamed "Royale".
2003|Royale demoed at Macromedia MAX.
2004|Flex 1.0 released in March.

Flex 1.5 released in November.
2005|Flash Player introduces new virtual machine that improves performance by an order of magnitude.

Development begins on Flex 2, a rewrite intended to leverage new Flash Player capabilities.

Flex 2 Alpha released at MAX in October.

Macromedia Labs introduced.

Adobe acquires Macromedia in December.
2006|Flex 2 released in June.
2007|Flex 2.0.1 released in January.

Adobe announces Flex moving to open source in April.

Flex 3 Beta released in June.

Public bug system goes live.
2008|Flex 3 released in February and open source site goes live.
2010|Flex 4 released in March.
2011|Flex 4.6 released in December
source

2012|Apache Flex 4.8 (parity release of Flex 4.6) released in July.