What apps/software do people use for drawings? [More info in post]

Xournal++ is a handwriting notetaking software with PDF annotation support. Written in C++ with GTK3, supporting Linux (e.g. Ubuntu, Debian, Arch, SUSE), macOS and Windows 10. Supports pen input fr...

Drawing Pad is a mobile art studio for all the ages where they can precisely create their own art using photo-realistic crayons, markers, paintbrushes, stickers, roller pens, and more.