I went to London recently. The mass transit there supports both an old-fashioned NFC Oyster card and a contactless pay-by-phone option. Culturally, it seems lik

I went to London recently. The mass transit there supports both an old-fashioned NFC Oyster card and a contactless pay-by-phone option. Culturally, it seems like the whole city is shifting toward the latter option. There's a huge convenience advantage in minimizing the number of objects that you have to carry, retrieve, and put away in your day-to-day life. In China, this trend is even more advanced: payment by facial recognition is widespread there. Is that such a bad thing? Think of how much more fluid life must be without commercial friction.