Awesome!! I really needed this. The other app in the store was nothing more then a wrapper and did not really worked well.
Other question, there is also TooterB (Mastodon client) and Wisperfish (Signal) in the openrepos.net. Are those apps easy to port to UbuntuTouch? Maybe Wisperfish not at first because there is a Signal desktop app in the store, but the Mastodon apps in the store do not really work (wrapper that not remember your password).
But again, awesome you port this proton mail bridge app.