Notable is a desktop note-taking app where everything is written in Markdown. Uses the same editor as VS Code, so you get multi-cursors, minimap, and solid syntax highlighting out of the box.
Core features
Notes and attachments are stored as plain files on disk. No proprietary format, no database. You can sync with Dropbox, use Git, edit notes with any other editor, or run regex search-and-replace across your whole library.
The editor supports KaTeX expressions, Mermaid diagrams, and has a built-in Markdown cheatsheet. There's a dark theme, zen mode for distraction-free writing, a split editor for live preview, and a multi-note editor for bulk operations like tagging or deleting.
Other highlights: fuzzy search, nested tags, quick open window, note-to-note linking, import from Evernote and Boostnote, export to Markdown/HTML/PDF.
Platforms
Available on macOS, Windows, and Linux. Web and mobile apps are in development (will require a paid subscription for cloud sync and E2E encryption). Desktop stays free.
Limitations
Development has slowed. The planned features (built-in sync, version control, plugins, mobile apps) have been "Future" for a while. The app works well as-is but don't expect rapid iteration.