Top Alternatives to Zimbra Desktop

Thunderbird is a open source mail client developed and maintained by Mozilla foundation.

Microsoft Outlook is a personal information manager from Microsoft.

Mailbird is a desktop email client for Windows 7, 8 and 10.

Apple Mail is an email client included with the operating systems macOS, iOS and watchOS by Apple Inc.

eM Client is a Windows based e-mail client for sending and receiving e-mails, managing calendars, contacts, and tasks.

Evolution is the official personal information manager for GNOME.

Postbox is powerful, intuitive, ultra-customizable, speedy task manager.

QupZilla is a free and open-source web browser, intended for general users.

UC Browser is a mobile browser developed by the Chinese mobile Internet company UCWeb.

Mailspring is a multi-platform email client.

Claws Mail is a free and open-source, GTK+-based email and news client. It offers easy configuration and an abundance of features.

EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries, etc.

The Bat! is an email program for Windows that protects the correspondence and empowers the users to handle large amounts of emails quickly and efficiently.

Airmail is a fast mail client for Mac and iPhone.

Mutt is a text-based email client for Unix-like systems.

Iridium Browser is based on the Chromium code base. All modifications enhance the privacy of the user and make sure that the latest and best secure technologies are used.

Slimjet is a fast and powerful web browser that is based on the Blink engine and is built on top of the Chromium open source project.

OpenProject is a web-based project management system for location-independent team collaboration.

KMail is the email component of Kontact, the integrated personal information manager from KDE.

Kontact is a personal information manager and groupware software suite developed by KDE. It supports calendars, contacts, notes, to-do lists, news, and email.

Feng Office is a commercial Open Source web based solution aimed to enhance collaboration and productivity.

AOL Mail (Aol Mail) is a free web-based email service.

Polymail is an email application for OS X and iOS known for its clean interface and additional features atop the Gmail platform.

Microsoft Mail and Calendar apps help you stay up to date on your email, manage your schedule and stay in touch with people you care about the most.

MailMate is an IMAP email client for macOS featuring extensive keyboard control, Markdown integrated email composition, advanced search conditions.