The Maryland House of Delegates approved a bill Thursday that would require retailers to tell customers when they track their movements and habits via mobile phones.
"It is alarming how much information a store can gather from your phone when you walk in the door," said Del. Sam Arora, a Rockville Democrat. "At the very minimum, we deserve to know when stores are tracking information from our phones."
Arora, a sponsor of the bill, said an estimated 1,000 retailers already use technology to track shoppers' movements through stores using mobile phone signals. Such use is expected to become more widespread over the next decade.
The technology can include video tracking designed to analyze shoppers' moods. In some cases, stores can link information from the cell phone signals to Twitter accounts or other sources to gather more specific information.
A hearing on a companion bill in the Senate is scheduled for March 19.