Source https://opensource.com/alternatives/gmail
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Related information https://www.oschina.net/news/66088/open-source-alternatives-gmail
https://webmail.phpnet.org/webmail-rainloop/Roundcube\Zimbra\zoho\SquirrelMail\Rainloop\Horde https://privmx.com, end-to-end encryption
Tutanota : https://tutanota.com this is Gmail encryption Rival openmailbox GroupOffice for all data .. its too fast compared to my gmail. https://www.group-office.com/ Protonmail.ch kmail penXchange Kopano is available in Debian, Ubuntu, OpenSuse and Fedora repositories V-webmail - PHP Based webmail application v-webmail.sourceforge.net/ https:/ /afterlogic.org/webmail-lite =============================== 4 Open Source Gmail Alternatives Let's Come see just a few free and open source webmail clients to choose from. Roundcube
The first is Roundcube. Roundcube is a modern webmail client that can be easily installed on a standard LAMP (Linux, Apache, MySQL and PHP) stack. It has a drag-and-drop interface that usually feels modern and fast, with an array of features: preset reactions, spell checking, translation into 70+ languages, a template system, tight address book integration, and more. It also has a pluggable API for creating extensions.
It comes with a comprehensive search tool, and some features on the roadmap, from calendar to mobile UI to conversation view, sound promising, but for now these missing features are slightly behind compared to some of the other options.
Roundcube is available as open source under GPLv3.
Roundcube
Roundcube screenshot courtesy of the project's website. The next client on the
Zimbra company list is Zimbra, which I use extensively for work.
Zimbra includes a webmail client and an email server, so if you're looking for an all-in-one solution, it might be a good choice.
Zimbra is a well-maintained project that has been hosted in many different corporate entities over the years and was acquired by Synacore in 2016. It has most of the features you'd expect in a modern webmail client, from webmail to folders for contact lists to some pluggable extensions, and generally works pretty well. I have to admit that the older version of Zimbra I am most familiar with can feel slow and clunky at times, especially on mobile devices, but it seems that newer versions have overcome these issues and provide a clear interface no matter what your equipment being used. The desktop client is also available for users who prefer a more local experience. For more information on Zimbra, see this article from Olivier Thierry of Zimbra, who sheds more light on Zimbra's role in the open source community.
Zimbra's web client is licensed under the General Public Attribution License, and the server code is available under GPLv2. small
Zimbra Inc.
Zimbra provides Clemente screenshots under the GNU Free Documentation License.
SquirrelMail
I have to admit, SquirrelMail (self-proclaimed "nut webmail") doesn't have all the features of some of the more modern email clients, but it's so simple to install and use that it's my go-to webmail tool. Over the years when I was building a website and needed an easy and "just working" mail client. Since I'm no longer doing client work and switching to forwarders instead of dedicated email accounts for personal projects, I realize it's been a while since I looked at SquirrelMail. For better or worse, it's exactly where I left it.
SquirrelMail started in 1999 as an early entry into the webmail client space, focusing on low resource consumption for both server and client. It requires few special technical extensions, as it was so important when it was created that browsers haven't standardized as much as we expected. The flip side of its somewhat outdated interface is that it's been tested and used in production for years, and for those who want a webmail client with little to no frills, but also few headaches to manage Nice choice.
SquirrelMail is written in PHP and licensed under GPL.
SquirrelMail
screenshot of SquirrelMail courtesy of the project website.
Rainloop
Next up is Rainloop. Rainloop is a very modern entry into the realm of webmail, and if you're used to using Gmail or other business email clients, its interface is definitely close to what you'd expect. It has most of the features you'd expect, including email address autocomplete, drag-and-drop and keyboard interface, filtering support, and many others, and can be easily extended with additional plugins. It integrates with other online accounts like Facebook, Twitter, Google, and Dropbox for a more connected experience, and it can also render HTML emails compared to some of the other clients I've used that you might encounter complex tagging issues.
It's very easy to install, and you can try Rainloop in an online demo to see if it's right for you.
Rainloop is primarily written in PHP, and the community version is licensed under the AGPL. You can also view the source code on GitHub.
Rainloop
Rainloop screenshot author.
More options
Mailspring is a new option that supports multiple accounts, read receipts, translation, undo send and other popular email client features. It was a fork developed by one of the creators of Nylas Mail, and it was maintained until Spring 2017.
Cypht is a lightweight email client and news reader written in PHP and JavaScript and licensed under the GPL v2. It was developed by the creators of HastyMail, an old GPL-licensed email client.
Mailpile is an HTML 5 email client written in Python, available under the AGPL. Currently in development, Mailpile focuses on speed and privacy.
WebMail Lite is a modern but minimalist option, licensed under the AGPL and written primarily in PHP.
Open WebMail is a GPL licensed client designed to provide efficient memory management for very large mail files.
kate was last on our list for this review, but it's now out of date. It's designed to go head-to-head with Gmail, and it's too bad the project isn't going anywhere.
There are also groupware solutions, like Horde, that offer webmail in addition to other collaboration tools.
This is by no means a complete list. What's your favorite open source webmail client?