Drawing in Symmetry with Autodesk Sketchbook
Drawing with automatic symmetry is a fun experience, and really enhances your drawing experience if you are creating a part of pattern, or something similar.
This is easy to do in Autodesk Sketchbook, as it has a stripped down interface, and is easy to understand.
I havee created two short demos of how easy it is to paint part of a pattern, with shading/color, in Sketchbook:
You can get Autodesk Sketchbook at: https://www.sketchbook.com/