Mid last month Starbucks added a new payment method. You can now go to Starbucks and pay with your phone via the Square wallet app which is available on both Android and Iphone. The service has launch at over 7000 Starbucks locations.
The Square Wallet app allows you to link your debit/credit card to the application. Then when you go to Starbucks you may simply tap the "Pay Here" button in the app or you scan scan a QR code to pay without reloading the available balances. This app also allows you to explore your area for any other business that allow you to pay with the Square Wallet app. It seems that Square is doing all that it can to compete with Google Wallet, Paypal app, and the Visa app. It will be interesting to see where mobile payments have gone in a few years.