so, these guys are saying,

1) Unlock phone
2) find app
3) open app
4) login
5) select card
6) select pump
7) prepay the amount (authorizes and charges the card)
8) wait for confirmation (biggest headache relying on cell phone data)
9) and then get out and fill fuel

is faster than get out, swipe card ?

I think the login aspect is very needed for security (or else anyone with the phone can pay for the fuel), but becomes a hassle (unlock phone with touch ID, unlock app with touch ID), when you always have your wallet with you.

If the app can be UX friendly, it'll certainly be a big boon for the cold months (and also reduce susceptibility to fraud at pump).