It’s a good time to master the basics of mobile money. Aready, smartphones can pay for Big Macs, Girl Scout cookies, and taxi rides. With the much-anticipated rollout of Google Wallet underway, some models will also be able to spend gift cards and pay at many more locations. Google Wallet and MasterCard PayPass, two examples of mobile money, work by storing your card data (from credit cards, prepaid cash cards, and loyalty cards) on your phone, then transmitting the info to the checkout stand when you wave or tap your device.