on the one hand, i'm an experienced flash developer, building OOP AS-projects using the Flash Builder.
on the other hand, i'm quite newbbie when it comes to flex. i made few text projects, just to get the hang of it, but i'm far from controlling all its capabilities.
many people ask me, what is actually the difference between a flash project and a flex project, and actually - i'm not sure i have the right answer with me.
can anybody help me with that?
For the end-user there's no difference between an application developed in Flash or in Flex (although you can sometimes recognize which one was developed with Flex and which wasn't).
The main difference is on the developer-side, Flex is a framework built on top of Flash that provides you a set of pre-built components. These components can help you create more complex and powerful Rich Internet Applications (RIA's) in less time. Components such as: Lists, DataGrids, TabNavigators, ToggleButtons, Forms, etc... will certainly help you develop any UI more rapidly thus leaving you more time to work in the app's logic layer.
Using Flex (or not using it) to develop an application depends on the needs and requirements of each application. If your application doesn't work with external/dynamic data, probably you will not need to use Flex... but that's always a developer decision =)