GIMP - GIMP is a multiplatform photo manipulation tool.
MyPaint - MyPaint is a fast, distraction-free, and easy painting tool for digital artists.
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.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Paint.NET - Paint.NET is a free image and photo editing software.
Corel Painter - Corel Painter is media painting software.