
Webseite: http://www.kdevelop.org/mediawiki/index.php/Main_Page
KDevelop 4 is a free, open source IDE for MS Windows, Mac OS X, Linux, Solaris and FreeBSD. It is a feature-full, plugin extensible IDE for C/C++ and other programming languages. It is based on KDE and Qt libraries and is under development since 1998. The 4.0 version has not yet included many of the features found in the 3.x version. The differences are listed at this website: KDev3 and KDev4 comparison table.
The Qt Assistant has been integrated into KDevelop 4 but the Qt Designer has not been, yet, and an available integration plugin to do that is not yet stable. The KDevelop 3.x IDE, integrated to the Qt3 API is no longer being supported but the IDE for Qt4 is not yet ready.
KDevelop has the qualities of Eclipse in that it tries to be a platform for several languages and tools, mainly via plugins, but its heart and soul is Qt. The appearance of QtCreator has diverted many users away from KDevelop, especially since QtCreator, devoted only to Qt/C++, has a better foundation for cross-platform application building.