It’s also probably worth noting that most of the stock iOS apps are the most service-provider-agnostic in the industry. Mail and Notes work on bog standard IMAP

It’s also probably worth noting that most of the stock iOS apps are the most service-provider-agnostic in the industry. Mail and Notes work on bog standard IMAP, and Calendar and Contacts are built on CalDAV and CardDAV, respectively. Google services work fine in all of them (though could be better if it weren’t for Google’s crappy IMAP implementation). The only case where they don’t work is with non-standard providers like Proton. Go try to sign into your open-standards-abiding calendar and notes accounts in the Calendar and Contacts bundled with nearly every Android phone on the planet and see how well that goes.