Walmart recently announced it is joining with a dozen retailers including Best Buy, Target, and 7-Eleven (MCX), a mobile-payments network that will compete with Google Wallet and mobile payment system Isis, which is supported by the major mobile carriers and . No launch date was given for the exchange, but development of MCXs mobile app, which will work on virtually any smartphone, is under way.

Like their competitors, the retailers plan to combine their mobile wallet with targeted offers and promotions offered to users on their smartphones.

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