Along with most other applications, KDE 4.2 development tools have been enhanced.

Vi and Vim editor support is now built into the KDE development platform with the Kate editor's text component, so apps like KDevelop and Kwrite can also support this.

The document viewer Okular is another application that has received some Vi-like features.

Okteta, a hex editor for the raw data of files, has a new view mode as an option. In this view mode, value and char meanings are shown next to each other, as an alternative to the traditional separation in columns. The decoding table tool now also lists int64 and UTF-8 values.

KDE 4.2 introduces experimental Python bindings support for the Marble widget and related classes. This means it is possible for KDE applications written in Python to make direct use of the Marble widget in their user interface to display an interactive map and to overlay custom information and rendering on top of it.