OpenScales is an Open Source (LGPL) mapping framework based on ActionScript 3 and Flex. It has been designed for building Rich Internet Mapping Applications easily.

OpenScales has been initially started from FlexLayers source code, donated by Scott Pezanowski. FlexLayers was a Flex port of OpenLayers. Since the beginning, the codebase has been extensively modified and improved. Nevertheless, even if OpenScales API is not strictly equivalent to OpenLayers one, if you have ever developed on OpenLayers, you will find OpenScales API quite easy to understand.