Should shoppers turn off their smartphones when they hit the mall, or does leaving them on lead to better sales or shorter lines at the cash register?

Retailers are using mobile-based technology to track shoppers’ movements at some malls and stores. The companies collecting the information say it’s anonymous, can’t be traced to a specific person and no one should worry that their privacy is being invaded. But consumer advocates aren’t convinced. It’s spying, they say, and shoppers should be able to choose whether to allow that.

The Federal Trade Commission held a workshop Wednesday on the issue. The FTC says it wants to better understand how companies are using phone-location technology, how robust privacy controls are and whether shoppers are notified in advance.

(AP)