The XMPP Standards Foundation

Develops and maintains the XMPP standard for instant messaging and voice and video calls. It’s a free open federated standard, so anyone can set up their own server or write their own app. (XMPP used to be known as Jabber.)

Fediverse address:
@xmpp@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

Fediphoto Lineage

An app for Android phones available through F-Droid which makes it as easy as possible to share photos on the Fediverse. It’s based on an app by PLA, who enjoyed sharing pictures on the Fediverse while out and about. PLA sadly died in January 2021, and Fediphoto Lineage aims to honour his memory by keeping his project alive.

Fediverse address:
@fediphoto_lineage@libranet.de

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

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

Collabora Office

Online fork of the LibreOffice productivity suite aimed at businesses, including long term tech support, admin tools, smartphone apps and cloud collaboration.

Fediverse address:
@CollaboraOffice@mastodon.social

Its development company, Collabora, is one of the biggest upstream contributors to LibreOffice’s source code, and has a close relationship with the FOSS community.

Fediverse address:
@collabora@floss.social

Snikket

XMPP-based free open federated messenger project. It aims to make XMPP into a more viable alternative to Whatsapp etc by providing consistency in design and terminology, while still maintaining compatibility with other XMPP apps and servers. (It’s a similar plan to how Mastodon made ActivityPub more mainstream while still being compatible with other ActivityPub server types.)

Fediverse address:
@snikket_im@fosstodon.org

AntennaPod

Free open source podcast player for Android devices. The app lets you listen to podcasts, keep track of episodes and manage your podcast subscriptions through open standards like RSS.

Fediverse account:
@AntennaPod@fosstodon.org

The Prototype Fund

Funding initiative of the German government promoting development of open software. Anyone can apply for funding who lives in Germany, is self-employed, pays German taxes and publishes their source code on some sort of source forge. (You don’t need German citizenship.)

Fediverse address (in German):
@PrototypeFund@mastodon.social

LibreOffice

The most popular free open source office suite, it includes a word processor, spreadsheet, presentation software etc. It’s very widely used by businesses, governments, organisations and individuals, and is available for Linux, Mac and Windows.

Fediverse address:
@libreoffice@fosstodon.org

There are also user groups on the Fediverse:

Fediverse address (in Spanish):
@LibreOfficeEs@mastodon.social

Fediverse address (in French):
@LaMouetteODF@framapiaf.org

KDE

Worldwide free open source software community which creates all kinds of popular useful projects such as the Plasma desktop, Kdenlive, Krita and lots more.

Fediverse address (main):
@kde@floss.social

Fediverse address (videos):
@kde_community@tube.kockatoo.org

Fediverse address (conference videos):
@kde@conf.tube

Fediverse address (Spanish language community):
@kde_espana@floss.social

Fediverse address (French language community):
@kdefr@framapiaf.org

FreeRCT

Free open source theme park game inspired by RollerCoaster Tycoon. The game uses entirely libre assets, so you don’t need any proprietary licences to play it. It’s still in alpha testing but playable.

Fediverse address:
@FreeRCT@floss.social

YunoHost

Version of Linux which makes it as easy as possible to install and maintain your own self-hosted online services. There’s a really easy graphical interface, it works on home servers or remote ones, and it supports older and lower powered computers too.

Fediverse address (main account in English and French):
@yunohost@mastodon.social

Fediverse address (video account in English and French):
@yunohost@cinema.yunohost.support

Goldfish

Brand new project trying to create a short video clip sharing service for the Fediverse (sort of a free open federated alternative to TikTok or Vine). It’s still in its very early rough draft stages, but is making steady progress.

Fediverse address:
@Goldfish@mstdn.social

WriteFreely

Free open source federated blogging platform. The interface and options are minimalist, with the focus on reading text with as few distractions as possible. It’s part of the Fediverse, so you can follow WriteFreely blogs from Mastodon etc. You can host a WriteFreely server yourself, or sign up on an existing server.

Fediverse address (main):
@writefreely@writing.exchange

Fediverse address (blog):
@writefreely@blog.writefreely.org

Senfcall.de

A free open source video conferencing site which aims to provide a privacy-friendly alternative to proprietary services. Calls are made through the web browser using the BigBlueButton platform.

Fediverse address (in German and English):
@senfcall@chaos.social

FreeTech Project

Non-profit initiative helping people use technology in a more financially, socially and environmentally sustainable manner, mainly relying on FOSS wherever possible. Provides help to everyone, regardless of technical skill level. Based in South Yorkshire, UK.

Fediverse address (main):
@freetechproject@floss.social

Fediverse address (videos):
@freetechproject@tilvids.com

Tails

A special version of Linux that aims for maximum privacy and anonymity. Tails runs entirely off a USB stick, it uses the Tor network to connect to the internet, and by default it resets/forgets everything you’ve done when you switch it off. (You can also optionally save encrypted data if you need to keep something.)

Fediverse address:
@tails@fosstodon.org

PublicSpaces

A non-profit coalition of Dutch broadcasters, museums, arts organisations etc. campaigning for an ethical internet. They organise conferences on this topic, and run their own Fediverse servers.

Fediverse address (main, in Dutch and English): @publicspaces@publicspaces.net

Fediverse address (videos, in Dutch and English): @publicspaces@video.publicspaces.net

Fediverse address (podcasts, in Dutch and English): @TheTimeIsNow@podcast.publicspaces.net

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

NextCloud

Free open source personal cloud software for sharing files, collaborative editing, instant messaging, personal music streaming and lots of other things. It’s extremely flexible thanks to lots of add-on apps that can be installed through the graphical interface. Nextcloud instances can be accessed through web browsers or dedicated apps for all major platforms. You can host a cloud yourself or sign up on an existing instance.

Fediverse address:
@nextcloud@mastodon.xyz

The Spritely Institute

Developing the next generation of Fediverse platforms, led by Christine Lemmer-Webber who co-authored the ActivityPub technical standard which the current Fediverse is built upon. (Previously known as the Spritely Project.)

Fediverse address:
@spritelyinst@octodon.social

Grow Your Own Services

Website from the creator of Fedi.Directory (that’s me!) which helps non-technical people create their own online services through managed hosting providers. Managed hosting means the hosting company does all the technical stuff behind the scenes, but you own and run the service. This allows anyone to make their own Fediverse servers, personal clouds, music streaming services and much more.

Fediverse address:
@homegrown@social.growyourown.services

Arthur Pizza

Videos mostly about technology, especially free open source software, Linux and PC accessories. The videos are a mixture of features, tutorials and news items. There are also some interesting wild card non-technical videos too.

Fediverse address:
@art@tilvids.com

Tusky

Free open source Mastodon app for Android phones, available through F-Droid and Google Play. Can also be used by other Fediverse platforms that use the Mastodon API such as PixelFed and GoToSocial.

Fediverse address:
@Tusky@mastodon.social

K-9 Mail

Very popular free open source e-mail app for Android. It is due to become the official Thunderbird app for Android devices.

Fediverse address:
@k9mail@fosstodon.org

Gancio

A free open source collaborative online calendar. It allows local communities to share a common calendar that anyone can post events to, even people without an account. (Posts are moderated to prevent spam though.) You can also interact with Gancio through the Fediverse, and it has RSS support for people who want to follow through feed readers.

Fediverse address:
@gancio@mastodon.cisti.org

E Foundation / Murena

The E Foundation develops and maintains a free open source privacy-friendly de-Googled version of Android, which you can either install yourself on your existing phone or buy pre-installed on a new phone. They sell pre-installed phones through the Murena brand, all of which are manufactured by established companies like Fairphone, Samsung etc.

Fediverse address (E Foundation):
@e_mydata@mastodon.social

Fediverse address (Murena):
@murena@mastodon.social