Ключевые слова: background, bar, barcode, bill, black, buy, cell, cellphone, checkout, code, commerce, concept, digital, display, electronic, hand, holding, id, identification, internet, label, message, mobile, money, online, pay, payment, people, phone, price, qr, qr code technology, qrcode, reader, restaurant, retail, sale, sales, scan, scanner, service, smart, smartphone, store, suit, tag, technology, telephone, touchscreen, transaction,