TeXstudio version 2.5.1 has been released. It's mainly a bugfix release. but also provides some new features, such as a new template system, a better fold panel, a context menu für in-text preview, and an option for opening all included documents.
TeXstudio is a fork of the popular LaTeX editor Texmaker, forked in 2009. At first it was called TeXmakerX because it began as a small set of extensions to Texmaker. Today, it's an independent program with significant differences to Texmaker.
Similar to Texmaker. TeXstudio is available for Unix/Linux (inluding BSD), Mac OS X, and Windows. Its license is GPL v2, and it's open source.