Hi, > What i read here and there is that the performances are poor. Don't believe everything you read. Performance is good for most use cases. Can you write 60 fps full 3d games will millions of polygons on the screen at once in Flex? Probably not but then that's not what it's for. There were some performance issue on mobile (scrolling big lists for instance) but that was greatly improved in Flex SDK 4.5 and 4.6 releases (and newer versions of AIR).
I really can't see any JS/HTML performing any better in the same situations where Flex has issues. Thanks, Justin