Sites like opendocument.app

Curbox, a free open-source Android app by Nethical for limiting phone screen time, blocking distracting apps and websites

A cross-platform tool for Fate/Grand Order players, with Chaldeas, a planner, and Laplace, a battle simulator

Stephen Paul Weber's personal website: blog essays on technology and inequality, software projects, standards work, and his resume

Weil Jimmer's personal blog on computer technology, covering programming, software, hardware and networking, with posts on AI agents and Docker Compose

Fedilab, a free open-source multi-account client for Mastodon, Pleroma, Friendica, Pixelfed and PeerTube, with documentation and related projects

Super Productivity, an open-source task manager and time tracker app for planning deep work and tracking time spent

UnifiedPush is an open-source, decentralized push notification system letting app developers and users choose their own notification service

Libretro, a project and website for the crossplatform application API behind the RetroArch emulator frontend, with news and forums

Gadgetbridge, a free open source Android app for pairing and managing smart watches, bands and other wearable gadgets without vendor apps

A German personal site by Andreas Itzchak Rehberg on Android books and coaching, plus Oracle database administration tips and services

A free, open-source webcomic by David Revoy, funded directly by its patrons, about a young witch and her cat

A program for running classic graphical adventure and role-playing games on modern systems, using the games' original data files

e Foundation, a nonprofit building open source, privacy-focused deGoogled smartphone operating systems and online cloud services

Tasks.org: documentation and product pages for Tasks, a free open-source Android task management app with CalDAV sync

Volksverpetzer, a German fact-checking blog and app debunking fake news and disinformation, run by its editorial team

Playnite, an open source video game library manager that unifies games from Steam, Epic, GOG and other stores

Thorium Browser, a fast Chromium-based web browser for Linux, Windows, macOS, Android and Raspberry Pi, with developer tools and demos by its maker

F-Droid is an app store and distribution platform for free and open source Android apps

SimpleX Chat: a private messenger app and network with no user identifiers, developed by the SimpleX team

Lubuntu, the official home of the lightweight Ubuntu-based Linux distribution using the LXQt desktop, with release announcements and community links

The Nobara Project is a Fedora-based Linux desktop distribution tuned for gaming, streaming and content creation, with downloadable ISO editions

Personal site of Brennan Kenneth Brown, a Métis writer and open-source web developer, with essays, books, and writing portfolio

Syncthing, an open-source continuous file synchronisation tool, with project donation and foundation information pages

The Battle for Wesnoth is an open source, turn-based fantasy strategy video game, with its project's developer documentation and release notes

BleachBit, an open-source disk cleaner and file shredder for Windows and Linux systems, with its help and documentation pages

The official website of Thunderbird, a free open-source desktop and mobile email, calendar and contacts app

Godot Engine, a free open-source 2D and 3D game engine with a project blog and forum, with news by Thaddeus Crews and others

A security-focused, compartmentalizing desktop operating system based on Xen, with project news, hardware compatibility list and documentation

Browsh, a text-based web browser by Tom Buckley-Houston that renders modern pages for remote servers over SSH or Mosh

Org Mode for GNU Emacs: a plain-text major mode and project site for notes, to-do lists, planning and literate programming

A BitTorrent client called Deluge, with GTK, web and console interfaces, for Linux, macOS, Unix and Windows

LibrePCB, a free open-source electronic design automation suite for drawing schematics and designing printed circuit boards, with a blog and documentation

Calibre, a free open-source e-book management software for converting, organising and syncing e-books across devices

An open source PlayStation 2 emulator project, with a website carrying its blog posts and project information

Joplin, an open source note-taking app with multimedia notes, web clipping and end-to-end encrypted sync, developed by Laurent

Rocket.Chat, an open source team chat and collaboration platform for secure, self-hosted government and enterprise communications

Personal academic website of Fredrik Johansson, researcher in computer algebra, covering his Arb arbitrary-precision library, publications and thesis

Nextcloud, an open source self-hosted platform for file sharing and online collaboration as a Microsoft 365 alternative

Manjaro, a Linux distribution built on Arch with rolling releases, with news and team pages by its core developers