I imagine one of those swipe attachments for a cheap android phone would work well. The UI is known pretty well now, and many people trust them in the US. I oft

I imagine one of those swipe attachments for a cheap android phone would work well. The UI is known pretty well now, and many people trust them in the US. I often see them at festivals, where it was previously all-cash, but are now maybe 20% plastic, usually for bigger items ($65 tshirts lol.)