Obsidian

Obsidian is the notes app for people who don't trust the cloud with their second brain. Local-first, markdown files on your machine, free for personal use, sync optional. If you've ever woken up to a Notion outage or worried about what happens when Evernote shuts down, Obsidian is the answer. Your notes are plain text files in a folder. They'll outlive any company. For founders the use case is personal knowledge management. Daily notes. Reading notes. Project plans. Decision logs. The kind of writing you do for yourself, not your team. Obsidian's killer feature is bidirectional linking with double-brackets [[like this]], plus a graph view that shows how your notes connect. Concepts emerge as you write rather than being pre-defined in folders. The community plugin ecosystem is enormous and is where Obsidian shines. Dataview turns your notes into a queryable database. Templater handles dynamic templates. Excalidraw embeds a whiteboarding tool. Tasks adds GTD-style task management. There's a plugin for almost any workflow, and the ones that matter are excellent. The community has built tooling that rivals or beats what commercial products ship. The pricing model is unusual and good. Obsidian itself is free for personal use, including for indie founders running businesses on it (the license is generous). Commercial use for teams of 2+ is $50/user/year, which is cheap compared to alternatives. Obsidian Sync is $4/month for cross-device sync; Obsidian Publish is $8/month for publishing notes as a website. The trade-offs: Obsidian is single-player. There's no real-time team collaboration (Sync handles cross-device for one user, not team collaboration). The mobile app is good but heavier than Apple Notes. The learning curve is real — Obsidian is the most powerful notes app on the market and the power comes from configuration. New users often bounce off because it feels too 'configurable' before it feels productive. My take: if you take notes for yourself and you value data ownership, install Obsidian. The free tier covers everything important. Add Sync at $4/month if you use multiple devices. Pair with Notion for team work; don't fight Obsidian's single-player nature for shared docs. For knowledge-worker founders who write extensively, Obsidian is one of the few tools that compounds in value over years. The notes you take this year are still searchable and link-able in five years. That permanence is the real value prop.