i prefer paying with my smartphone or a watch , this is the "new" way.
My understanding, barter is the most ancient trade method in the world, not something new.
I don't think he means giving a smartphone in exchange for a service, but rather, using your phone like a credit card, via something like Apple Pay or Google Pay. It'll forward the payment to your card.
exactly, he means just that. These new payment methods make me paranoid! you never know if you are truly safe from fraud, especially when your device is stolen. better to use other types of payments, perhaps with something that gives you more security and control of your finances