With Flex 4 you can easily add color and life to your web applications by introducing dynamic user features, slick transitions, and eye-catching animations. Flex also provides powerful data handling capabilities so you can build industrial-strength applications. And it's open source, so you can get started without forking over a lot of your hard-earned cash. We think it should be just as much fun to learn Flex as it is to use Flex. Hello! Flex 4 shows you everything you need to know to get started with Flex 4 without bogging you down in obscure detail or academic edge cases. In this entertaining, hands-on book, you'll quickly move from Hello World into the techniques you'll need to use Flex effectively. You'll start by progressing through 26 self-contained workshop items, which include everything from small one-page examples, to a 3D rotating haiku, to building a Connect Four game. Finally, in the last chapter you'll build a full Flex application called 'SocialStalkr': an interesting mashup of Twitter and Yahoo Maps that lets you 'stalk' your friends by showing specially formatted Twitter tweets on a Yahoo map.