The software doesn't require a large amount of memory, so it runs very quickly and is agile. Moreover, it is expandable, meaning that is is possible to develop external tools in C++ or Java using Bouml. These external tools are known as plug-outs.
Bouml also allows you to work with UML 2 and has support for a large amount of diagrams. It can also generate documentation in several formats like XML or HTML.
If you're looking for a UML 2 tool, Bouml can be an ideal option. Its great features and the fact that it's free thanks to the GPL license make it a really worthy alternative for this task. Download Bouml for free, it's the ideal solution to model software systems.