I needed to get better organized.

Concepts

sketching tool with layers and vector manipulation

• https://concepts.app/en/ios/manual/
• https://concepts.app/en/ios/support (videos)

Inkscape

for vectors

• https://inkscape.org/learn/tutorials/

Krita

for raster images with/without vector editing tools

• https://docs.krita.org/en/user_manual/getting_started.html

mtPaint

• https://mtpaint.sourceforge.net/handbook/en_GB/chap_00.html

Paint.NET

for rasters

• https://forums.getpaint.net/forum/18-tutorials-publishing-only/

Pencil2D

for hand-drawn animations

• https://www.pencil2d.org/doc/tutorials.html

Updated 2 Nov 2023.