At open@adobe [1] is nice description of flex which could be used after 
some tweaking:

Apache Flex is a highly productive, open source application framework 
for building and maintaining expressive web applications that deploy 
consistently on all major browsers, desktops and devices (including 
smartphones, tablets and tv). It provides a modern, standards-based 
language and programming model that supports common design patterns 
suitable for developers from many backgrounds. Flex applications run in 
the ubiquitous Adobe® Flash® Player and Adobe® AIR™.


[1] http://sourceforge.net/adobe/flexsdk/wiki/About/