Well, I had to try it…

Interesting: some apps like Audible which have settings to only download while on WiFi really stick to just that - they won’t download if the phone is connected to Ethernet. Others like Downcast are fine with it, though they have the same kind of WiFi-only preference.

I assume some are checking “not cellular” and some are checking “on WiFi” perhaps? I know nothing about iOS apps, curious though!

@Nick_Craver the apps can check for Wi-Fi or for wired ethernet, typically every app just checks for Wi-Fi ignoring wired ethernet because it is not very common.