Fastmail provides one of the most secure and reliable email environments in the industry. Rock Solid Reliability. More safety.

No-frills, easy to use, easy to maintain Email client for Android based on the JSON Meta Application Protocol (JMAP).

All your E-mail, from all your accounts, in one place. Cypht is like a news reader, but for E-mail. Cypht does not replace your existing accounts - it combines them into one. And it's also a news reader :).

The Cyrus IMAP server differs from other IMAP server implementations in that it is generally intended to be run on sealed servers, where normal users cannot log in. Users can access mail through the IMAP/IMAP-S, JMAP, POP3/POP3-S or KPOP protocols.

Group-Office is an enterprise CRM and groupware tool. Share projects, calendars, files and e-mail online with co-workers and clients. Easy to use and fully customizable.

James stands for Java Apache Mail Enterprise Server! It has a modular architecture based on a rich set of modern and efficient components which provides at the end complete, stable, secure and extendable Mail Servers running on the JVM.

Stalwart is an open-core mail server solution with JMAP, IMAP4, POP3, and SMTP support and a wide range of modern features. It is written in Rust and designed to be secure, fast, robust and scalable.