K-9 Mail

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FastMail

Tutanota is the world's most secure email service, easy to use and private by design. Tutanota brings secure email for everybody.

World's largest secure email service providing end-to-end encrypted email accounts. ProtonMail is based in Geneva, Switzerland and protected by Swiss privacy laws. The software is openly developed with fully open source code.

Zoho Mail provides ad-free email hosting for business and organizations. It's comes with intuitive migration tools, along with 24/7 dedicated migration support to ensure smooth, lossless migration from your existing email provider. With Zoho Mail, your organization can manage all their email, calendar and contact needs. Since Zoho Mail is part of the Zoho's suite of online productivity, it's easy to extend the capability in to more parts of Zoho's offering and essentially run your entire business with Zoho. Zoho is provided as a Freemium software, where the free plan supports up to 5 users in an organization.

Arguably the most popular email service in the world, Gmail provides a email inbox for over 1.5 billion users. With Gmail you can create an email account for free that manages emails and contacts in the same application. Gmail is web-base but provides clients for mobile devices and supports third-party programs that synchronize email content through POP or IMAP protocols.

A free an open-source email client developed openly by the Mozilla Foundation and the community. Thunderbird is easy to setup and customize and supports POP and IMAP. The email client comes with all features needed to search, filter, write and manage emails, but also have builtin support for live chat between contact and RSS/Atom feed reader.

World's largest secure email service providing end-to-end encrypted email accounts. ProtonMail is based in Geneva, Switzerland and protected by Swiss privacy laws. The software is openly developed with fully open source code.