GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!
Quokka (formerly Kryptowire) - The gold standard in SAST, MAST, IAST, and more!
Grade My Email - Helps you get out of the spam folder.
HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
Email Marketing Academy from MailerLite - Learning platform for email marketing expert certification
Platformly - Platformly is a suite of tools for multi-channel marketing automation.