Best new learning, design and developer resources: 17 October

The directory additions from 17 October were thirty free tools and websites plus ten open-source projects from GitHub. This roundup groups them into notes and everyday utilities, learning and research, design resources, finding more tools, PDFs and data, and developer and AI agent projects. Features and pricing change, so check each tool's own page before you commit.

Notes, automation and everyday utilities

Trilium Notes is a free, open-source note-taking app that organises notes in a deep tree with labels, relations, templates and full-text search. It works offline on your desktop and supports rich text, code, canvas, mind maps and encrypted notes, but it has no official mobile app and syncing needs a server you host yourself. Etherpad is a free, open-source editor where several people write in the same document at once, each in their own colour, with chat and a time slider to replay changes; you can self-host it or use a public instance, whose reliability varies.

AutoHotkey is a free, open-source scripting language for Windows that creates keyboard shortcuts, text expansions and small automations, and Everything, from voidtools, indexes file and folder names on Windows and shows results instantly as you type; by default it searches names, not file contents. CopyQ is a free, open-source clipboard manager with a searchable history, tabs, tags and custom commands. On the Mac, AltTab brings Windows-style window switching with a preview of every open window; the core switcher is free, while search and extra styles need an optional Pro licence.

World Time Buddy lines up several cities side by side to find a meeting time that suits everyone; the free version covers a handful of locations and shows ads. A Soft Murmur is a free website for mixing ambient sounds such as rain, waves and coffee-shop chatter, with a timer that stops or fades the sound. calibre is a free, open-source e-book manager that organises your library, converts between formats such as EPUB, AZW3 and PDF, and syncs books to e-readers, though it cannot open books protected by DRM.

Learning, typing and research

Khan Academy is a non-profit offering free lessons, practice exercises and videos from early school level to university, with mastery-based practice but no accredited certificates. freeCodeCamp is a non-profit with free, self-paced curricula in web development, JavaScript, Python and data analysis, built around interactive exercises, real projects and free certifications. MIT OpenCourseWare publishes lecture notes, videos, problem sets and exams from thousands of MIT courses with no sign-up, though there is no grading and some recordings are older.

Exercism is a free, open-source platform for practising programming in more than 70 languages, with automated feedback and free reviews from volunteer mentors, whose waiting times vary. Keybr is a free typing tutor that builds lessons around your weak keys and tracks detailed statistics. For research, Connected Papers builds a visual graph of papers related to one you enter, which helps with literature reviews; the free plan includes a limited number of graphs each month.

Icons, colours, illustrations and images

Iconify brings together more than 200,000 icons from open-source sets in one searchable library and shows each set's licence, which differs from set to set. Remix Icon is a free, open-source set of more than 3,000 neutral-style icons in outlined and filled versions, free for personal and commercial projects. Hero Patterns offers repeatable SVG background patterns with adjustable colours and opacity, and favicon.io generates a favicon and app icons from text, an image or an emoji, with the HTML code to add them.

Adobe Color builds palettes with a colour wheel and harmony rules, extracts themes from images and checks contrast and colour-blind safety; saving palettes needs a free Adobe account. Openverse is a free, open-source search engine for more than 800 million openly licensed and public domain images and audio tracks, run as part of the WordPress project; it does not verify licence details for you, so check each work before reuse. Storyset, from Freepik, offers customisable illustrations with simple animations, with attribution required on the free licence. Lapa Ninja is a gallery of more than 7,000 landing page designs for inspiration, and PhotoGIMP is a free, open-source patch that makes GIMP 3 feel familiar to Photoshop users, though it needs GIMP installed first and does not add Photoshop-only features.

Finding more tools

There's An AI For That is a free directory of thousands of AI tools that you can search by task, with pricing details, ratings and alternatives; the layout is busy and includes sponsored listings. SaaSHub is an independent marketplace for finding and comparing software alternatives, with reviews and pricing notes, and featured listings appear near the top. DevHunt is a free, open-source launch platform where the community upvotes new developer tools each week, many of them early-stage.

PDFs, file conversion and data

iLovePDF handles everyday PDF jobs such as merging, splitting, compressing, converting, signing and protecting files; the free web version has file size and usage limits and uploads files to its servers, so think twice before using it for sensitive documents. CloudConvert converts between more than 200 formats with adjustable quality settings and a daily number of free conversions. JSON Crack is a free, open-source tool that turns JSON, YAML, CSV and XML into an interactive graph in the browser, where you can also format, validate and query data.

Open-source developer and AI agent projects from GitHub

Ten free, open-source projects were also added. Whiteboard is a desktop canvas where you and an AI coding agent such as Claude Code or Codex design software together with diagrams, semantic diffs and decision logs; files cannot be edited inside the app yet, and anonymous telemetry is on until you turn it off. reladraw is a text-based diagram language that sits between Mermaid and draw.io, and diffle is a keyboard-first diff viewer for reviewing Git diffs and GitHub pull requests in the browser, then handing comments to an agent or posting them as a pending review.

MockServer mocks HTTP, gRPC, WebSockets and AI chat APIs from one port for testing, and k10s is a Kubernetes terminal UI that works with the mouse and includes an AI assistant. Harness Terminal is a GPU-rendered macOS terminal that notifies you when a coding agent stops or asks for approval; it needs an Apple silicon Mac on macOS 15 or later. explainroo lets a coding agent produce narrated explainer videos and needs Node.js and ffmpeg, Big Arrow on the Screen lets agents draw arrows and notes over any macOS window to show where to click, and Screen Memories searches your photos and videos on a Mac by plain-language description, running every model locally. Langchain.rb is a Ruby gem that gives Ruby and Rails developers one interface for many language model providers, whose costs are separate. These are third-party projects provided as-is by their maintainers, so review each project's licence, code and security before installing.

You can browse every one of these, along with the rest of the collection, in the full directory, where filters for pricing, platform and category help you narrow things down.