The technology made by U.K.-based Path Intelligence Ltd. uses sensors around the mall to detect cellphone signals and track them as they move around the building. Chris Keane/Reuters

Two U.S. malls are using Black Friday to start testing technology that tracks customers as they shop by homing in on their cellphone signals.

Promenade Temecula in Southern California and Short Pump Town Center in Richmond, Va., will continue gathering data about shopper behaviour through the holiday shopping period until New Year's Day, said a news release from Cleveland, Ohio-based Forest City Commercial Management, which owns the two malls. Signs have been posted to notify shoppers.

The system will provide the malls with information about shoppers' length of stay and shopping patterns, such as whether they will go out of their way to visit a specific store or whether shoppers visit several similar stores to compare items and prices, the release said.

Using the data, the malls can relocate certain stores to make their locations more convenient and address congestion, figure out what other retailers should be added, what kinds of events and what promotions are most effective for attracting shoppers, said Stephanie Shriver-Engdahl, vice president of digital strategy for Forest City, in a statement.

The cellphone tracking technology, called Footpath, is made by Path Intelligence Ltd., a Portsmouth, U.K.-based company. It uses sensors placed throughout the mall to detect signals from mobile phones and track their path around the mall. The sensors cannot gather phone numbers or other identifying data, or intercept or log data about calls or SMS messages, the company says.

The technology has already been deployed at malls in Europe and Australia, tracking about one million customers a day. A spokesperson for Path Intelligence said the company has not been in talks with any malls in Canada, and the technology has never been deployed there.