Mailu - Mailu is a simple yet full-featured mail server as a set of Docker images.
Listmonk - Send e-mail campaigns from a powerful dashboard. High performance and features packed into one app.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
Sendy - Sendy is a self hosted newsletter app that sends emails 100x cheaper via Amazon SES
MailEnable - MailEnable is a Windows based mail server and email server program that is packed with the state of the features and functions like antivirus and spam filtering system, webmail management system, cardDAV, CalDAV and much more.
MailChimp - MailChimp is the best way to design, send, and share email newsletters.