On: The paper passport's days are numbered

[woodruffw]

You're going to use an app over a landline?

[whimsicalism → woodruffw]

if my app has a code, presumably they're equally able to verify it over a landline

[woodruffw → whimsicalism]

Sure, assuming the phone isn't dead. I've also been in disaster-stricken places where that wasn't a certainty.