AT&T today launched AT&T Alerts, an opt-in, geo-location text messaging alerts service that will enable consumers to receive offers such as discounts, rewards and promotions from nearby retailers.

Offered free to consumers, the AT&T Alerts is available without the need to download an app. Consumers who opt-in are located once entering a retailer's geo-fence, which is a virtual perimeter tied to a real-world location. A user’s device location is determined using cell tower signals, not the GPS, and the location of the device is then matched to existing geo-fences, the announcement said.

Several brands, including Gap, Staples, Zales, Last Call by Neiman Marcus, Duracell, Motorola and Discover are participating in the nationwide service. The program will work on all AT&T phones, excluding the iPhone 5.

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