Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
RealWorld Photos - RealWorld Photos is an free portable photo editor for Windows.
Autodesk SketchBook - SketchBook drawing and painting software provides designers, architects, and concept artists the tools to sketch ideas quickly and create beautiful illustrations.
Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
Clip Studio Paint - The artist's software for drawing and painting.
SoftColor PhotoEQ - SoftColor PhotoEQ makes color correction, image editing and color management tasks simpler.