Samsung's <005930.KS> Nexus S phone, based on the latest version of Google's Android software, will go on sale this month in the United States and Britain through Best Buy and Carphone Warehouse .

The two retailers said they would be the exclusive sellers in those two markets of the Nexus S, which supports a technology that lets people use their handsets instead of credit cards for payments, and would take pre-orders from 1600 GMT on Monday.

Google's Android software has rapidly overtaken Apple and BlackBerry to become the second most popular platform worldwide after Nokia's Symbian, and the most popular in North America and east Asia.

Offered free to cellphone vendors since coming to market two years ago, Android has helped fuel a boom in the smartphone market, which is expected to double this year to about 340 million units, although it has helped drive prices down.

The Nexus S will include an NXP near-field communications (NFC) chip, which allows consumers to pay for items by tapping the phone against a special terminal.

NXP, a pioneer of NFC technology, announced a strategic collaboration with Google to provide a complete open source software stack for the NFC chip.

Carphone and Best Buy said they would offer the Nexus S unlocked for $529 in the United States or for $199 with a T-Mobile contract.

In Britain, it will cost 549.95 pounds ($862) unlocked, or will come free with a contract of 35 pounds per month for a term and with an operator yet to be announced.

The previous flagship Google Android phone, the Nexus One, was made by Taiwan's HTC <2498.TW>. Samsung has also produced a tablet computer based on Android, the Galaxy Tab.

Deals with Carphone Warehouse and Best Buy underline the importance of independent distributors beyond operators to Google, British telecoms research firm CCS Insight said. Despite the initial failure of Nexus One, Google's intent clearly remains unchanged.

U.S. consumer electronics retailer Best Buy and British mobile phone retailer Carphone Warehouse have a joint venture in Europe that includes stores in Britain, and a chain of Best Buy Mobile stores in the United States.

(Editing by David Holmes)

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