I'll be honest, I havent tested it on phones at all but i'm not surprised its not well handled. I'll see if i can do a usability pass on mobile but I don't think it will be a priority for now
No worries. I'm impressed how well Godot handles mobile as it is. Pixelorama and GodSVG for example is pretty good.
Your tool comes at a pretty interesting moment for me as alpha builds of official Blender on Android are coming out now. It sorta works around the issue with multi tapping, but still.
I know I'm an oddball using a phone as my main dev environment so no pressure ^_^.
I tested on an android tablet and unfortunately it doesn't seem to create depth for any shapes
Tried with touchscreen/stylus/mouse
edit: looks like a workaround is after placing the (flat) shape you can then add the depth with face mode.
its an extra step compared to PC, but at least its not completely unuseable