Octarine: free lightweight Markdown/Obsidian-like app for Mac

Posted by MadaboutDana
Sep 24, 2025 at 09:24 AM

Since first writing about Octarine I’ve been following the app’s development with considerable interest and have finally gone Pro.

The developer, Rajat, has now decided to focus on Octarine full-time. He’s added a heap of features (multi-tabbing, multiple windows, AI assistance (including support for on-device AI models running on e.g. Ollama), a very good search function, etc. It also supports tagging and has a rather nice Daily Note function which allows you to transfer yesterday’s list of tasks to today’s. And he’s just introduced properties and folding headers. More details at: https://octarine.app

It’s already available for Mac, Windows and Linux, and now he’s working on an iOS version. Personally, I’m also hoping for an Android version, simply because I’ve moved away from iOS for my mobile needs.

Why does this app interest me? Above all because it’s a very fast equivalent to e.g. Obsidian in a small fraction of the footprint – Octarine’s disk footprint is just 27 MB. In this day and age, that’s extraordinary! And Rajat, who’s a software engineer, is very responsive and enthusiastic.

Rajat would love to join us on Outlinersoftware, but despite applying, never received the “confirm your identity” notice. Any ideas on that?