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Browser: Safari (FF as backup browser)
Mail: Outlook
Calendar: Outlook
They work. Mail/cal sync works across devices. Outlook for mac has some shortcomings but broadly works.
I also have ProtonMail (free) in a browser when I want a change
 
Browser: Safari and Firefox
Mail: Apple Mail app (Gmail is my email provider but I don't use app)
Calendar: Apple calendar app (Gmail calendar disabled)
 
I use Firefox as the browser because i love the refresh icon at the bottom of the screen. So easy to refresh a page.

I use the iOS included mail and calendar apps.
 
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