The pitch on the page is "Notepad x VS Code x Evernote, divided by 10" and honestly that is about right. It is a notes app for people who live in code. The editor is Monaco, the same engine VS Code uses, so it feels familiar the second you open it.
You can open local files and edit them directly, or keep notes that sync through a dedicated folder in your own Google Drive. The app only touches that one folder, which I appreciate. Syntax highlighting covers over 50 languages, and the Markdown preview handles GitHub Flavored Markdown plus Mermaid diagrams. There is full-text search and a side-by-side editing mode too.
The current version is 1.7.1, with downloads for Mac and Windows on GitHub and companion apps for iOS and Android that share the same Drive folder, so your notes follow you around. If you take a lot of notes and you write code, this one is worth a look.
Product page: https://jun-murakami.web.app/apps/monaco-notepad