Ever since Adobe decided to move Flex into the Open Source world late last year, many people have been involved in discussions about the companys move. This decision has made some people think that Flex is dying.
When I mention Open Source to almost anyone other than a computer expert, its likely that the response will be: Whats Open Source?
To try and put it in simple words, Open Source software is free and generally available on the internet. It is also normally distributed with its underlying code, or source code, which a knowledgeable programmer can read and modify to meet specific business needs; unlike commercial software that is sold only in a compiled executable version.
Nowadays many people are giving HTML5 a shot instead of Flex because they think its the technology that is going to stick, but it may still be too early to switch. Most of them dont pay much attention to the fact that, at the time this post is being written, fewer than 5 percent of browsers support HTML5. A simple search on the internet will give you several reasons to reconsider, or at least think twice, before going ahead with HTML5 as an alternative to Flex. This will most definitely change in the next couple of years, but even then it is likely that we go through a few HTML5 iterations before it is widely supported.
I am a believer that a war between the technologies should never occur. Anyone who rules out one of the technologies is not necessarily doing you a disservice, but, as for any project, the pros and cons should always be considered. There will always be the argument to use Flex for several reasons, such as the code is much nicer, and it has far better object-oriented and pattern support.
Many people are apprehensive about Open Source, but you will find Open Source in plenty of places and being used in many very successful projects.
So whether you choose to use Flex or any other technology, make sure your decision will be the one to cater best for your needs: the best RIA (Rich internet Application) available for your timeline and budget.