For example, American Eagle offers Foursquare users a 15 percent-off coupon when they check-in to stores nationwide.

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The deal with American Express is similar to a service that Foursquare launched with American Express at South By Southwest that enabled people to get deals by paying with American Express.

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Foursquare also has done a deal with American Express so that consumers can sync their credit cards to Foursquare to get special deals.

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The deals with Mastercard and Visa represent an extension of a partnership Foursquare has had since 2011 with American Express.

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This partnership is the first for Foursquare with a company as big as American Express.

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You can do the loyalty piece without payments, as Foursquare has done, but even Foursquare is tying loyalty in with companies like American Express.

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American Express stresses that it does not share data on its members' spending habits with Foursquare.

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And American Express Card members can unlock even more deals by checking into participating dineLA restaurants via the social networking site Foursquare.

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