Best new markdown, privacy, focus and developer resources: 15 October

15 October brought a mix of free tools and free alternatives to popular apps, plus ten open-source projects from GitHub. I've sorted them into notes and Markdown writing, passwords and privacy, images, PDFs and diagrams, focus and time tracking, research, and developer projects. Features and pricing change, so check each tool's own page before you commit.

Notes and writing in Markdown

Heynote is a free desktop scratchpad for macOS, Windows and Linux. It keeps one persistent text buffer split into blocks, and each block gets its own language and syntax highlighting. Maths blocks double as a calculator with variables and unit conversions. There's no mobile app or cloud sync, and the licence is source-available rather than fully open source.

Standard Notes is an open-source notes app that encrypts everything end to end. The free plan gives you plain text notes, unlimited device sync, offline access, two-factor authentication and daily encrypted email backups. Rich text, folders and encrypted file storage are paid.

For Markdown, MarkText is a free, open-source desktop editor with a live preview that renders headings and emphasis right where you type. It also has focus and typewriter modes and exports to PDF or HTML. StackEdit is a free, open-source editor that runs in the browser with a side-by-side preview, and it can sync or publish to Google Drive, Dropbox and GitHub. Development has slowed in recent years, though. HedgeDoc, formerly CodiMD, lets several people edit the same Markdown note in real time from a shared link. For regular use you'll need your own server, and the public demo isn't meant for important notes.

Open Knowledge is a free, open-source Markdown editor and wiki that keeps your notes as plain Markdown while letting language models read, write and organise them. It's an early-stage project aimed at technical users.

Keeping passwords and files private

Bitwarden stores passwords, passkeys and secure notes in an encrypted vault that syncs across devices. Its free plan covers unlimited passwords on unlimited devices; the built-in authenticator and file attachments are paid. KeePassXC goes the other way. It's a free, open-source password manager for Windows, macOS and Linux that keeps everything in an encrypted database file you control. No cloud, no account, no subscription. Syncing between devices is up to you, and there's no official mobile app.

Cryptomator creates encrypted vaults inside Dropbox, Google Drive, OneDrive or any synced folder, encrypting files and file names with AES-256 on your device. The desktop app is free and open source, and the full mobile apps are paid. With any encryption or password tool, keep a safe backup of your master password or keys. Lose them, and you can lose access to your data.

Images, PDFs and diagrams made easy

Squoosh is a free, open-source image compressor from Google Chrome Labs that runs entirely in your browser, so your images never get uploaded. It works on one image at a time. TinyPNG compresses images online and often cuts file sizes by more than 80%. Its free web tool takes up to 20 images at a time, each up to 5 MB, and uploads are deleted within 48 hours. Smallpdf has online tools to compress, convert, merge, split, edit and sign PDFs, with a daily download limit on the free plan.

tldraw is a free online whiteboard that opens straight in the browser, with shapes, arrows, sticky notes and real-time sharing by link. Keeping boards long term needs an account. draw.io, also known as diagrams.net, is a free, open-source diagram editor for flowcharts, mind maps, network and UML diagrams, and it saves to your device, Google Drive, OneDrive or GitHub.

Staying focused and tracking your time

ActivityWatch is a free, open-source time tracker that records which apps, window titles and websites you use, no timer needed, and it keeps the data on your own device. Clockify is the manual option: timers and logged hours across projects and clients, with a free plan that includes unlimited users and projects. Invoicing and advanced approvals are paid.

Pomofocus is a simple online Pomodoro timer that keeps tasks and estimates in one browser tab, with reports and integrations on the paid plan. myNoise gives you tunable rain, cafe, white noise and other ambient sound generators to drown out distractions. OneTab is a free browser extension for Chrome and Firefox that turns all your open tabs into a single list you can restore later.

For research

Zotero is a free reference manager. It saves papers, articles and web pages from your browser, keeps PDFs and notes in one library and creates citations in thousands of styles for Word, Google Docs and LibreOffice. Free cloud storage for PDFs is capped at 300 MB. The Internet Archive is a free, non-profit digital library of books, films, audio, software and images, and its Wayback Machine shows you old versions of websites. Many of its books can only be borrowed for a limited time.

Open-source developer projects on GitHub

Ten free, open-source projects from GitHub came in as well. DBX is a database client that connects to more than 100 databases from a single 25 MB app. Databasus is a self-hosted tool for scheduled PostgreSQL backups with point-in-time recovery and restore checks. Sync-in is a self-hosted platform for file storage, sharing and sync. Traceway puts logs, traces, metrics and session replay into one self-hosted observability tool. And Homelable draws a visual map of a homelab and keeps an eye on the status of each service.

For AI coding, Loop Engineering collects patterns, starter templates and CLI tools for running coding agents in repeatable loops. Pi Subagents adds sub-agents and parallel workflows to the Pi coding agent. Claude Code: Everything You Need to Know is a free, text-based course on Anthropic's Claude Code across three levels. UX/UI Agent Skills is a collection of design-system skills that steer Claude toward accessible, consistent interfaces. These are third-party projects provided as-is by their maintainers. Self-hosted tools need you to run, update and back them up, so review each project's licence, code and security before installing.

And that's only some of what's been added lately. Browse the full directory and filter by category, type, pricing and goal to find the right fit for your work.