What are some alternatives?
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.
MyPaint - MyPaint is a fast, distraction-free, and easy painting tool for digital artists.
PaintTool SAI - Learn to draw in different ways.
Clip Studio Paint - Powerful drawing and illustration tool.
GIMP - GIMP is a multiplatform photo manipulation tool.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.