Apple and Google Pay work without needing a connection, fortunately. What happens here quite often is that payment terminals fail so sometimes you're in a restaurant or bar and cannot pay your bill.
I've been living a completely cashless life since Google Pay was released. Wouldn't go back. Germany isn't fully there yet, especially restaurants and bars, but we're getting there.
Here in Sweden they even changed all the bills and most of the coins in 2016 because they needed to be "modernized". Nowadays most stores don't even take cash and I know many tourists/foreigners complain about it.
