So many people don't get this
So many lame comments around the idea of planning to steal money via a backpack mounted scanner or the 'advantages' of cash in wallet.
If you plan on skimming 'money' from NFC phones, then you might want to stop and think about what the hell you are saying. You are not stealing money, just sets of data bits - assuming you have valid merchant codes of course.
Good luck on spending those bits - depending on scheme implementation, there is generally a reconcilation process that takes place overnight as part of a settlement process so that the cash you spent on topping up your phone or when you pay your phone account is actually passed to the merchant. Generally people who look after cash and payments take it pretty seriously if they see any potential holes or flaws, so contactless smartcards have been around a long time now without anybody actually seriously exploiting them at least compared with the about of cash that gets stolen in any given day.
People not seeing the point probably don't see the pain points in areas like mass transport or sports events where you need to get hundreds or thousands of people very quickly through choke points and bloody oldtimers dicking around with coins and notes are a pain to everybody. Not to mention the hassle of parking meters/vending machines/coffee vendors etc for people like myself who rarely carry cash.
Yes, you have to deal with issues like multiple competing card formats, but right now I have 3 or 4 contactless cards on me. I would guess that most people do these days even if they are not aware of it, but how many people know what is stored on those cards?
I would rather that instead of people issuing more smartcards to me, they simply talked to my phone and used the smartcard in that. Means that I can check balances and transactions with a decent screen, can have more control - i.e maybe set it to play a 'ca-ching' sound everytime a transaction is made - things that existing smartcards can't do (and cash won't warn you of pick pockets either). If I lose my phone, I could remote wipe/disable (with the bonus of setting of alarms if somebody attempts to use the phone).
And yes.. I have worked in this area in the past, so most of the comments above do strike me as being from people who don't have a clue what they are writing about.
That being said, I think it needs critical mass from somebody like Visa/Mastercard/Apple to make NFC useful; it has to become ubiquitous, built into all new phones and payment terminals to really displace other forms of payment.