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.
Documentator - We make documenting your product a piece of cake 📘
Autodesk SketchBook - SketchBook drawing and painting software provides designers, architects, and concept artists the tools to sketch ideas quickly and create beautiful illustrations.
UnMarkDocs - Unleash the Power of Markdown to Write Better Product Documentation
Clip Studio Paint - The artist's software for drawing and painting.
Archbee.io - Archbee is a developer-focused product docs tool for your team. Build beautiful product documentation sites or internal wikis/knowledge bases to get your team and product knowledge in one place.