> I forgot a third development, which is thanks to Stripe and other mobile-friendly payment processors. All you need is a smartphone, and they send you a mini c

> I forgot a third development, which is thanks to Stripe and other mobile-friendly payment processors. All you need is a smartphone, and they send you a mini card reader that plugs into your phone. Did you mean Square? They were one of the first (if not the first) payment processors, iirc, to make it easy for merchants to offer card-swipe to customers, via the mobile phone attachment you mentioned.