Gimp Toolkit for X11 GUI (current stable version)

https://www.gtk.org/

Gimp Toolkit for X11 GUI (current stable version)

https://www.gtk.org/

C++ wrapper for gtk, a x11 graphics library

C++ wrapper for Gtk+, Pango, Atk, and Glib

http://gtkmm.sourceforge.net/

C++ wrapper for Gtk+

https://www.gtkmm.org/

GNOME virtual file system

https://www.gnome.org/

Shared libraries for Amateur Radio Equipment Control Applications

https://sourceforge.net/projects/hamlib/

Window manager designed for speed and usability

https://ice-wm.org/

Font by John Stracke based on the Isabella Breviary

https://www.thibault.org/fonts/isabella/

Low latency audio server

https://jackaudio.org/

JSON (RFC 4627) interface for Glib

http://live.gnome.org/JsonGlib

General purpose dynamic array

https://judy.sourceforge.net/

System to administer web accounts for the KDE desktop

https://projects.kde.org/projects/kdereview/kaccounts-integration

Digital camera manager for KDE

https://www.kde.org

Letter order game for KDE

https://www.kde.org/applications/education/kanagram

Pac-Man Clone

https://www.kde.org/applications/games/kapman/

Basic editor framework for the KDE system

https://kate-editor.org/

Sokoban-like Logic game

https://www.kde.org/applications/games/katomic/

Blackbox Logic game

https://www.kde.org/applications/games/kblackbox

Falling Blocks game

https://www.kde.org/applications/games/kblocks/

Ball Bouncing game

https://www.kde.org/applications/games/kbounce/

Breakout-like game

https://www.kde.org/applications/games/kbreakout/

KDE application to exercise fractions

https://www.kde.org/applications/education/kbruch

Scientific calculator for KDE

https://utils.kde.org/projects/kcalc/

Character selector for KDE

https://utils.kde.org/projects/kcharselect/

KDE application to select colors from the screen or from a palette

https://www.kde.org/applications/graphics/kcolorchooser

Mobipocket plugins for Strigi indexing and thumbnails

https://invent.kde.org/graphics/kdegraphics-mobipocket

SVG KPart

https://www.kde.org

KDE Filesharing via Samba

Show nice dialog boxes from shell scripts

https://kde.org

Three-in-a-row game

https://www.kde.org/applications/games/kdiamond/

Bookmark Organizer and Editor

https://kde.org

KF5 Framework for searching and managing user metadata

https://api.kde.org/baloo-index.html

KF5 workspace and cross-framework integration plugins

https://api.kde.org/frameworkintegration-index.html

KF5 runtime and library to organize work in separate activities

https://api.kde.org/kactivities-index.html

KF5 statistics for activities

https://api.kde.org/kactivities-stats-index.html

KF5 library that provides classes for handling archive formats

https://api.kde.org/karchive-index.html

KF5 text completion helpers and widgets

https://api.kde.org/kcompletion-index.html

KF5 widgets for configuration dialogs

https://api.kde.org/kconfigwidgets-index.html

DAV protocol implementation with KJobs

https://api.kde.org/kdav-index.html

KF5 extensible daemon for providing system level services

https://api.kde.org/kded-index.html

KF5 porting aid from KDELibs4

https://api.kde.org/kdelibs4support-index.html

KF5 integration of Frameworks widgets in Qt Designer/Creator

https://api.kde.org/kdesignerplugin-index.html

KF5 integration with su for elevated privileges

https://api.kde.org/kdesu-index.html

KF5 abstraction to system DNSSD features

https://api.kde.org/kdnssd-index.html

KF5 library to convert emoticons

https://api.kde.org/kemoticons-index.html

KF5 library to add support for global workspace shortcuts

https://api.kde.org/kglobalaccel-index.html

KF5 addons to QtGui

https://api.kde.org/kguiaddons-index.html

KF5 library for handling icons in applications

https://api.kde.org/kiconthemes-index.html

KF5 library providing support for additional image formats

https://api.kde.org/kimageformats-index.html