I find google surely belonging to the A-category. The host gmail. http://smallbusiness.chron.com/set-up-gmail-business-email-domain-10563.html tells about their options to link it to your own business domain.
But why not use the mail hosting from the ISP you select for your Android forum to be?
Kees
Why i can found A category Hosting for my E-Mail.Please help me.

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