Using multiple Snapper cards Place any Snapper card to the back of your Android NFC smartphone whenever the phone is unlocked, and the Snapper Mobile app will display the balance on that card. If you’re having trouble reading a Snapper card, it’s simple to check whether you’ve got a supported card. If you can’t see a ‘+’ sign in the top right-hand corner on the front of the card, get in touch via in app support and we’ll replace your old Snapper card for free.