What framework are the mobile apps using? ReactNative? Native?

[offsky]

I know that the desktop app is build with Electron. I was wondering what the mobile apps are built with? As far as I know Electron cannot directly target iOS/Android, so maybe something else is being used, like ReactNative or Capacitor. Or maybe there is a way to have Electron apps installed on iOS. If this is the case, I would love to know.

[CawlinTeffid]

Capacitor.

Why does fs.writeFile not save file?

Only the desktop version of Obsidian uses electron, the mobile version uses capacitor. this.app.vault.create("output.json", jsonContent); would be the correct function call you can omit the options as shown by the ?, they contain stuff that is not necessary here. https://marcus.se.net/obsidian-plugin-docs/api/interfaces/DataWriteOptions