Yeah I wasn't saying ecash bad because web browser rather just use ecash in a more secure way.

Could make a GUI wallet: https://github.com/AndyObtiva/glimmer

I don't know anything about how to program an ecash mint though.

A concern I have about ecash though, I would personally make each ecash mint distinctly different to avoid one mint going bad causing all mints to be diluted. This is because of Gresham's law. You know, make each ecash token wallet clear as to which mint it belongs to.