Introducing Google Wallet 
The Vision: Google Wallet is an Android app turning your mobile phone your wallet by storing virtual versions of your existing payment cards on your phone. You can simply tap your phone to pay and redeem offers using a technology near field communication, or NFC 
Payments, coupons, loyalty and more: Designed for an open commerce ecosystem, Google Wallet will eventually support most, if not all of the cards you currently keep in your wallet. But because its a mobile app, it will do more than a regular wallet ever could, like storing thousands of payment cards and Google Offers but without the bulk. Eventually your loyalty cards, gift cards, receipts, boarding passes, tickets, even your keys will be seamlessly synced to your Google Wallet. And every offer and loyalty point will be redeemed automatically with a single tap via NFC.
The future of commerce: When it launches, you’ll be able to use Citi® MasterCard® cards and the Google Prepaid Card with Google Wallet. You’ll be able to tap to pay at hundreds of thousands of merchants.
At launch, Google Wallet will be compatible with Nexus S 4G by Google, available on Sprint. Over time, there will be an expanding support to more phones.
This is just the beginning, but we believe that, in time, your phone with Google Wallet will be the one thing that holds everything you need to carry.