Zoho Mail

Their free plan is the best way to start with a professionnal email.

Since the professionnal email is hosted on Zoho, it can't be used in android apps like Gmail. However their Zoho Mail app for android works great and I really like it.

* SETUP AND ADMINISTRATION:
The Zoho Mail software service was a breeze to set up through the intuitive online portal. While you have a powerful authority and control oveer the technical details of your configuration, the administration portal gives a balanced level of abstraction and sensible default parameters to make the setup process quick and easy.

* EASE OF USE, OPEN STANDARDS AND EXTENDED FEATURES:
Zoho does not get in your way. All the standard protocol options are available, which makes this solution compatible with any mail user client software you prefer to use, from any web browser or the optional cross platform downloadable Zoho email client, or any standard mail (POP/SMTP) client you wish. There are no proprietary nor complicated modifications to the standard mail protocols.

* SELF SERVICE AND DEPENDABLE
The entire platform is self service from advanced administration and configuration, to daily usage at the user level. I have never had to call tech support in all the years I have been using the service, and I have never noticed any disruption to service nor any issue with availability of the service.

* SECURITY OPTIONS:
There are several methods supported for keeping your mail secure so only authorized access is granted once authenticated. Basic auth, multi-factor, and others if I recall correctly. There are options to delegate administrative rights to users as needed also.

Im summary, Zoho does not restrict the control you have over your email service and provides straight forward options for managing your service, is consistently reliable, and rich in features that you can add or remove yourself, as needed. It just works!

Disclosure: I am using the personal entry level offering from Zoho. This makes the service all the more impressive to me, because it has continued flawlessly for years in my case, as if I were on a bigger business plan with strict SLA's. I might be mistaken, but I believe Zoho had all of this functionality and powerful control long before any of the bigger names in email services did, and even today I believe the others will be more expensive to unlock the features Zoho provides out of the box on the entry level plan.

It’s extremely difficult to sign in—the passwordless sign-in methods often crash, making it feel like winning the lottery when you actually manage to log in.

so far nothing I like it, I am trying to sign in the account for this whole week, but unluckily I still can not sign in.

Custom domain emails, free plan that's relatively flexible. App is wonderful, so is their desktop client.

They're slowly inching their model to less free options.