Credit card company Visa and clothing retailer Gap announced last month that they're using SMS text messages to deliver updates about promotions and discounts to Gap customers' mobile phones.

The system, which uses Visa's global processing network, will be expanded to retailers nationwide, Visa said, although no timeline was announced.

Gap and Visa began a pilot of the real-time text message system in November. Customers enroll via a secure website and are sent Gap offers when they use Visa cards to complete transactions that meet certain criteria -- for example, if they buy something at a store in a specified ZIP code. Once the offers appear on their phones, the customers can take advantage of them by showing the text messages to Gap sales clerks.

Visa said that high-speed transaction processing helps retailers reach potential customers with new offers while they're still out shopping.

Amy Carr, director of customer relationship management strategy at Gap, said the Visa system has given the retailer new insights into its customer base, leading to improvements in the way it targets promotions to people.

This version of this story was originally published in Computerworld's print edition. It was adapted from an article that appeared earlier on

Read more about mobile and wireless in Computerworld's Mobile and Wireless Topic Center.