Square Wallet lets you leave your real wallet at home when you go shopping. Square Wallet knows when you're in a store and gives the clerk permission to make a charge to your account.
Small shops, artisans, and cookie-toting Girl Scout troops have used Square credit-card readers for a few years now. The magnetic readers plug into smart phones and tablets, giving merchants an easy and mobile way to accept credit cards. But Square has bigger plans.
It imagines using people's smart phones as fingerprints. When customers walk into a shop, their phone will wirelessly "announce" their presence. The cash register will know their name, face, and preferred payment method. When the shoppers approach the cashier, they can charge their purchase to the credit card on file simply by saying their name. The salesclerk checks the profile photo to make sure that it matches the person there, and can then approve the transaction. No wallet or signature required.