Email Hosting Providers

FreshdeskFreshdesk

Freshdesk Usage Statistics · Download List of All Websites using Freshdesk

An online help desk software that allows you to support customers over email

CRM

SPFSPF

SPF Usage Statistics · Download List of All Websites using SPF

The Sender Policy Framework is an open standard specifying a technical method to prevent sender address forgery.

Standard

Google Apps for BusinessGoogle Apps for Business

Google Apps for Business Usage Statistics · Download List of All Websites using Google Apps for Business

Web-based email, calendar, and documents for teams. Renamed to Google Apps for Work, but now known as G Suite From Google Cloud.

Business Email Hosting