Free open source XMPP app for Linux and Android, and part of the KDE project. Includes OMEMO support for end-to-end encryption.
Fediverse address:
@kaidan@fosstodon.org
Tagged: E2EE
Prav App
Free open source encrypted XMPP app for Android produced alongside a member-funded XMPP service, currently in private beta testing. Developed and run by a co-operative based in India.
Fediverse address:
@prav@venera.social
Gajim
Free open source XMPP desktop app for Linux, Mac and Windows. Includes OMEMO end-to-end encryption support.
Fediverse address:
@gajim@fosstodon.org
Monal IM
Free open source XMPP messenger app for iPhone, iPad and Mac. It includes support for OMEMO end-to-end encryption.
Fediverse address:
@Monal@fosstodon.org
Delta Chat
Free open source end-to-end encrypted messaging system that works through email. This means if you both have Delta apps running you can chat in encrypted mode, but even people without Delta can chat with you through their normal email account. It’s available for Android, iOS, Linux, Mac and Windows.
Fediverse address:
@delta@chaos.social
Dino
Free open source XMPP/Jabber app for Linux which includes support for end to end encrypted messaging, voice/video calls and conferencing.
Fediverse address:
@dino@fosstodon.org
Jami
Free open source end-to-end encrypted peer-to-peer calling and messaging app. It supports video calls, audio, messaging and has a Skype-style interface. It has apps for all major platforms including Android, iPhone/iPad, Linux, Mac and Windows.
Fediverse address:
@Jami@mstdn.io
Briar
Free open source end-to-end encrypted peer-to-peer messaging system for Android and Linux which can be used online through Tor, or locally through wifi or bluetooth. Because it has local support it can be used even if the internet is shut down or broken, for example at demonstrations or in disaster zones.
Fediverse address:
@briar@fosstodon.org
Tuta (formerly Tutanota)
Independent privacy-friendly email and calendar provider which is ad-free and paid for entirely by their users’ subscriptions. There are free open source apps for Android, iOS, Linux, Mac and Windows. There’s also support for E2EE and 2FA wherever possible.
Fediverse address:
@Tutanota@mastodon.social
CryptPad
Privacy-friendly free open source online office suite. It can be self-hosted, or you can use the official instance. It’s collaborative and anonymous, with “zero knowledge” encryption so no one can access your data except you and those you choose to share with.
Fediverse address:
@cryptpad@fosstodon.org
Cryptomator
Free open source app that lets you add an end-to-end encrypted folder to your existing cloud service. It works with popular cloud services such as Nextcloud, DropBox, Google Drive, One Drive, iCloud etc. There are apps for Linux, Mac, Windows, iPhone/iPad and Android.
Fediverse address:
@cryptomator@mastodon.online