A few simple thoughts about QR codes. NFC fails on some advertising... advertising on a metro system? Your advert is likely to be the other side of some high v

A few simple thoughts about QR codes. NFC fails on some advertising... advertising on a metro system? Your advert is likely to be the other side of some high voltage train tracks, no-one could scan the NFC, but people can still scan a QR code from that distance. For transactions printed QR codes are a poor choice. A lot of the time transactions want to prove that you are there performing the transaction. As an example, think of payments and cardholder-not-present... the magnetic stripe and the chip on a debit card both hold more information (just a few extra bytes) than the 16-digit number printed on a card. It is possible to prove the debit card (and implicitly 'you') were there. With QR codes someone is able to take a photo of a QR code and then scan it again else where. It's very hard to prove you were there for the sake of a transaction. Ignoring payments, think FourSquare check-ins that are tied to promotions where check-ins are done via QR scanning at a café, you're giving away a deal based on something you cannot prove and is open to fraud. QR codes do help with transactions that don't require security, and with storing a fair amount of info in a dense area. Think vcards stored in a QR code on badges in a conference, or a bicycle with security QR stickers declaring ownership located in places where a bike mechanic would find them (under innertube on wheel rim, inside handlebars)... the ubiquity of QR readers (pretty much all smart phones) makes them ideal for communicating a small chunk of data to anyone and not requiring specialist equipment to read that data. Where QR codes have weaknesses are related to storage of hidden data, and different values per instance of a code. Financial transactions depend on this to prove cardholder is present, and stock management depends on this to accurately count stock. QR codes have their place (advertising, conference badges, tagging things, small chunks of dense data), and NFC has it's place (transactions, stock management). Sometimes these use cases overlap (conference badges) but mostly they do not.