MuPDF 1.28.5 is an AGPL document engine that reads PDF, XPS, EPUB and comic archives, ships a light viewer called mupdf-gl, and bundles nineteen command line tools for rendering, conversion and signing. The tag was cut on 25 September 2026.

ONLYOFFICE Desktop Editors 10.0 gathers AI into a module you install or leave out. DOCX, XLSX, PPTX and PDF open in one window, and the source is published under AGPLv3.

Logseq is an open source knowledge base where every line is a block: inline it into an outline or point at it from another page. Daily notes, card review and queries cover writing, revisiting and gathering.

Word processing, spreadsheets, presentations, drawing, databases and formulas in one free package, maintained by a foundation rather than a vendor, with documents that save to an open format by default.

Write a Python expression in a cell instead of a nested formula, and get back a number, an array or a figure. The whole scientific stack is importable, so the grid doubles as an executable notebook.

Most mapping tools spend their effort on looking good. Freeplane spends it on being capable: nodes carry attributes, formulas, dates and priorities, and a filter can hide everything that does not answer the question you are asking.

Combining dozens of scans into one file, or breaking a thick volume into chapters, is the most ordinary request in the world and the one most often mishandled. PDFsam Basic does both locally, with no limit, no watermark and nothing uploaded.

Anytype writes to the device first, syncs between devices over an encrypted peer to peer network where relays only forward ciphertext, and organises everything as objects that can relate to each other. Open source, free for personal use.

Standard Notes is an open-source note app with end-to-end encryption that has been running for more than ten years, with a public codebase and independent security audits. The permanently free tier covers encryption, unlimited devices, offline access, tags, per-note passwords, daily encrypted backups and two-step verification, and every note can leave as plain text.

A to do list that lives in the terminal: one command records a task, another brings it back. Tasks carry projects, tags, priority, dates, estimates and dependencies, repeating items are defined once, and the whole store is a file on your own machine.

Tasks as ordinary lines of text with priority, dates, projects and contexts: readable by people, parsed by scripts, and portable between every editor and system you will ever use.

The long-running open source office suite from the Apache Foundation: Writer, Calc, Impress and three more components cover the working day, the ODF format it carries is an international standard, no licence fee is charged on any system, downloads have passed 330 million, and the current release is 4.1.16.

A free open source reader for Windows that also opens EPUB and MOBI books, comic archives and DjVu, comes as a single file portable build, and weighs about 10.6 MB for the 64 bit installer. Version 3.6.1.

A minimal open-source text editor for Windows 10 and 11 with a Fluent Design interface, tabbed documents, live Markdown preview, a difference viewer and automatic session snapshots. MIT licence, no advertising, no tracking.

An open source, self-hosted notebook organised as a tree rather than a flat list. Notes can be cloned into several branches, edited in place with tables, diagrams and formulas, scripted with JavaScript, and reached through a REST API. Run the desktop client or your own server.