I'd like to propose having a list of groups in the mobile app, that shows tick boxes for toggling chat and notifications ("notices") off and on. Plus a quick toggle for turning all on, or all off. Maybe a bit like this...

This is for when logged in on the app, notifications while logged out is a different matter and we already have that.

I don't know which category to use for this... would have liked a Canny category like "UX".