Apps similar to Zimbra Collaboration Suite include Microsoft 365 Copilot, which has a free version. Other options are Google Workspace, Roundcube, eigen and mailcow: dockerized. Mail Servers like Zimbra Collaboration Suite are a crowded field, with more than 50 alternatives for the web, Linux, self-hosting, Windows and Mac.
Sendmail is a general purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol (SMTP) used for email transport over the Internet.
United States
Hub For Teams gives you and your team 100% control of your data and workspace. Enjoy enterprise collaboration features such as project management, discussion rooms, and much more.
South Korea
Vietnam
Office EU is a 100% European office suite with email, documents, calendar, and cloud storage. Open-source, GDPR-compliant, and free from foreign jurisdiction.
Netherlands
EU
inbuxa is a JMAP-first mail and collaboration server: JMAP, CalDAV, CardDAV and WebDAV in one binary, with IMAP, POP3 and ManageSieve supported until you switch them off. It ships with its own administration console and webmail, installed together as one suite.
United States
