Google Wallet is a free app that makes your phone into an all-in-one device for finding offers and paying for items.

Field-testing in New York and San Francisco will start today and debut everywhere this summer in partnership with Citi, MasterCard, First Data and Sprint.

Google Wallet has enabled the service to use multiple cards, including store loyalty accounts, with a single account. It requires a pin to use the app, then the information is sent to your bank for verification, then sent to a services manager — the only company that sees your credit card data. Once you set it up, you can only use up to $100 before entering an authorization code that’s e-mailed to you.

The chip has a lot of security features that sound like they come out of a spy movie — the chip will self-destruct if it’s tampered with and is protected against laser attacks. When the screen is off, so is the NFC. Personal information is only accessible when the Wallet is unlocked.

Google will also have a pre-paid card available in every account and allow any Wallet user to tap and pay at any of thousands of PayPass locations. Users can add funds to the Google card from any credit card.

Companies joining Google in this first push include American Eagle, Subway and Macy’s. You can also get deals in these stores by tapping your phone on ads in participating stores..

In addition to Google Wallet, the company also announced the launch of Google Offers. Google will offer a deal of the day as well as check-in offers, offer ads, real-time offers and offers through a business’ places page. The service will start in Portland, Ore., San Francisco and New York.

When you search for a product, if you click on an offer related to that search, you can add the coupon to your Wallet and it will update on your phone immediately. At the point of sale, the Wallet will pass on the relevant information to the register in one tap.

Google said that Wallet will be compatible with Sprint’s Nexus S 4G by Google. “Over time, we plan on expanding support to more phones,” Google said in a blog post.

What do you think of a mobile wallet? Will you consider ditching your wallet for an NFC-enabled phone?

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