Krita - Painting and Image Editing
With a full feature-set, configurable gui and a strong focus on plain productivity, Krita is at home on every artist's desktop.
Krita is a creative sketching and painting application based on Calligra technology. Whether you want to create art paintings, cartoons, concept art or textures, Krita supports most graphics tablets out of the box. Krita has relied on Qt's graphics tablet support since Krita 2.0. We consciously dropped our own X11-level code in favour of the cross-platform API that Qt offered.