The Best of the Best Email Apps!

I find rating email clients to be very subjective. --Maybe more so than any other Application.

With that said, my choice is Bare Bones Software's Mailsmith. It has BBEdit's great text-munging capabilities, a very clean interface and it does NOT do (nor ever will, according to BBS) HTML mail. It's filter & scripting capabilities are second-to-none. Not to mention BBS's great tech support (should you ever have a problem with the program, need help in creating a script, or wish to log a feature request for a future update to the program.)

--Mailsmith and BBEdit are old friends. I could not imagine my day-to-day computing without them.

Personally, I like Eudora Pro. I have been told that Apple's Email is good - especially the upgrade in 10.2
13 year old thread, all of a sudden comes back to life.
It's a miracle! - and for completely wrong reasons, too...
I guess that Eurold (?) and Nine are not iOS, but Android apps.