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!
Listmonk - Send e-mail campaigns from a powerful dashboard. High performance and features packed into one app.
Quokka (formerly Kryptowire) - The gold standard in SAST, MAST, IAST, and more!
Sendy - Sendy is a self hosted newsletter app that sends emails 100x cheaper via Amazon SES
HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
Mailman - Mailman is free software for managing electronic mail discussion and e-newsletter lists.