[musicale]

> all apps have internet access by default, and you cannot stop it

Technically you can by turning off wi-fi and disabling cellular data, bluetooth, location services, etc. for the app.

To your point though, wi-fi data should also be a per-app setting, and it is an annoying omission. macOS has outgoing firewalls, but iOS does not (though you could perhaps fake it with a VPN.)