Thunderbird

Thunderbird is a free, open source, cross-platform e-mail, news and instant messaging client. The project strategy is modeled after Mozilla Firefox.

Free Open Source Mac Windows Linux BSD PortableApps.com ... Haiku

Extensible by Plugins/Extensions Built-in RSS reader Built-in Calendar Calendar integration ... Categories Customizable Extensible by Plugins/Extensions Free API Gmail integration Google Calendar integration Import from Google Reader Support for IMAP Integrated Chat Integrated Password Manager Integrated Web Browser IOS support Legacy addons support Multiple Account support Export to OPML Import feeds from OPML POP3 Support Portable Secure file sharing SMTP integration Tabbed interface Support for Themes Add a feature

1779 Like

Evolution

Evolution is the official personal information manager and workgroup information management tool for GNOME. It combines e-mail, calendar, address book, and task list...

Free Open Source Linux BSD S/MIME GNOME OpenPGP

Built-in RSS reader CalDAV Calendar integration CardDAV ... Encrypted email Integrated Spam Protection Multiple languages POP3 Support Add a feature

150 Like

Geary

Geary is an email application built for GNOME 3. It allows you to read and send email with a simple, modern interface.

Free Open Source Linux BSD GNOME

Multiple Account support Add a feature

72 Like

Claws Mail

Claws Mail is an email client (and news reader), based on GTK+, featuring Quick response Graceful, and sophisticated interface Easy configuration...

Free Open Source Windows Linux BSD

Lightweight Built-in RSS reader Content Filtering Customizable ... Extensible by Plugins/Extensions Support for IMAP Multiple languages Multiple Account support Add a feature

76 Like

Mailspring

Boost your productivity and send better email with Mailspring, a beautiful, fast email client for Mac, Windows, and Linux. Mailspring is free to use and an optional pro...

Freemium $ $ $ Open Source Mac Windows Linux Arch Linux Fedora ... Ubuntu

Dark theme Multiple Account support Email tracking Sync Contacts ... Customizable Drag n drop Email Analytics Email tracking & analytics Extensible by Plugins/Extensions Support for IMAP Support for Themes Threaded Conversations Unified inbox Add a feature

29 Like

Mutt

Mutt is a small but very powerful text-based mail client for Unix operating systems. Some of its features are: color support, message threading, MIME support (including...

Free Open Source Mac Windows Linux Xfce

Command line interface Support for IMAP POP3 Support S/MIME support Add a feature

51 Like

Sylpheed

Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client (mailer, MUA). Sylpheed runs on many systems such as Windows, Linux, BSD, Mac OS X and...

Free Open Source Mac Windows Linux BSD PortableApps.com

Lightweight Add a feature

51 Like

Kontact - KMail

KMail is the email component of Kontact, the integrated personal information manager of KDE. Kontact is a personal information manager and groupware software suite for...

Free Open Source Mac Windows Linux BSD

No features added Add a feature

32 Like

Trojitá

Trojitá, is a fast Qt IMAP e-mail client that respects open standards and facilitates modern technologies. Trojitá values vendor-neutrality that IMAP provides...

Free Open Source Windows Linux

IMAP debugging Support for IMAP QT Based Add a feature

12 Like

Zimbra Desktop

The free Zimbra Desktop client allows you to meld the online and offline worlds – storing and synching your email, calendar, contacts, files and documents in the cloud...

Free Personal Mac Windows Linux

No features added Add a feature

29 Like

Kontact

Kontact is the integrated Personal Information Manager of KDE. Kontact suite unites mature and proven KDE PIM applications under one roof. Thanks to the powerful...

Free Open Source Windows Linux

Convert Email to Task Add a feature

25 Like

Pantheon Mail

Pantheon Mail is a free open source email client forked by the elementary OS community from Geary...

Free Open Source Linux elementary OS

Multiple Account support Add a feature

7 Like

sup

Sup is a console-based email client for people with a lot of email. It supports tagging, very fast full-text search, automatic contact- list management, custom code...

Free Open Source Linux

Command line interface Console-based Multiple Account support Responsive design Add a feature

11 Like

Do you think these apps are alternatives?

• Shift

  Shift is an email client that makes navigating between Mail, Calendar, Drive + your favorite Apps & Extensions easy (for Gmail, Outlook.com - Office 365 & Hotmail). .

  boomerang cross-account-search electron email-client extensions

  

  YES NO