Great option to other image editors and image creating software. It has a simple and intuitive user interface, yet supports both layers and 3D objects. Functional across all major OS. It is free, as in open source. It imports .PDN files created with Paint.NET without issues.
MyPaint - MyPaint is a fast, distraction-free, and easy painting tool for digital artists.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
GIMP - GIMP is a multiplatform photo manipulation tool.
Sketch - Professional digital design for Mac.
Microsoft Paint - Paint (formerly Paintbrush) is a simple, ultra-basic graphics painting program that is included...
Invision - Prototyping and collaboration for design teams