I’m still testing a few. The following list is favorite to least favorite after a month or so of use:

Skiff (free version - 10GB storage) - Using webmail is easy and straight forward, cell app is about the same. REALLY like that you basically get 4 email accounts (1 main and 3 alias account names), which is different than the others below. With the different aliases, this gives me an option to use Skiff for everything (if I choose to put it all in "one basket” - for personal, business and purchases/spam type uses). No integrated calendar, but significantly larger storage is a big plus. Otherwise, separate calendar app is fine, and they seem to be regularly making improvements. They also just implemented: “Quick Aliases are on mobile! Looking to protect your identity on mobile? You can now claim maskmy.id domains on mobile and use them to create privacy-protecting aliases that forward to your Skiff account.”

Tutanota (free - 1GB) - Using webmail is easy and straight forward as well, cell app about same. Main problem is, I’m never going to say “my email is xxxxx@TUTAmail.com” to anyone I know, especially business acquaintances. Name just sounds like something my mother or grandparents were scammed into using. They just changed the name from Tutanota to Tuta for some reason, so they could have taken the opportunity to come up with something different. However, the integrated calendar is nice, instead of a separate app. I’ve always swiped right to delete an email, but that’s archive on this app, and there is no option to change it. It’s been requested to have this option coded in (which it has been on Skiff) from others for year/s prior and no change has been made, so not expecting a lot of updates / improvements going forward.

Proton (free - 1GB, 500MB before doing 4 “tasks”) - Using webmail, cell app and separate calendar are all fine, I just prefer the other two so far.