Google opened its smartphone wallet to the public. Shops taking part in the programme began letting people pay for purchases with taps of Nexus S 4G smartphones from US telecom carrier Sprint.

“With Google Wallet, you can tap, pay and save using your phone and near field communication,” said Osama Bedier, vice president of payments at the Internet giant.

Google Wallet uses an NFC chip embedded in a smartphone to allow a user to “tap-and-pay” for purchases at a checkout register equipped with the PayPass system from CitiMasterCard.

Wallet software is being sent to Sprint Nexus S 4G phones in the form of an automatic over-the-air update.

“Simply install the app and the next time you spot one of the more than 300,000 PayPass locations around the globe, you’ll be ready to go,” gdgt.com co-founder Ryan Block said in a blog post at the MasterCard website.

Google and Sprint along with financial partners Citibank and MasterCard began testing Wallet in May.

Wallet initially works with the Nexus S 4G smartphone from Sprint and will eventually be expanded to more Android phones.

Wallet will be accepted by more than 300,000 merchants around the world.

NFC technology is being tested or used in a number of countries already, notably France, but Wallet will be the first to bring it to the US on a potentially large scale.

Stephanie Tilenius, Google’s vice president for commerce and payments, has described Google Wallet as the “next generation of mobile commerce.”

In addition to allowing for mobile payments, Wallet allows consumers to pay using gift cards and to redeem promotions such as discounts or coupons.

Google has been beefing up local content and services as online lifestyles increasingly revolve around smartphones with location-sensing capabilities.

Wallet essentially acts as a copy of a credit card stored on a smartphone, with no account data ever being put on Google servers.