Soon, walking into Los Angeles Union Station could prompt a highly personalized cellphone message that goes something like this: "Welcome to Union Station. For the Metro Red Line, take the escalator to your right."

The Metropolitan Transportation Authority is developing a plan to place as many as 50 tiny wireless devices in the downtown station that would push text message-like alerts to smartphones.

Metro officials say so-called beacon technology is a cheap, efficient way to communicate with passengers on a device they're probably already using. If the pilot program goes well, the beacons could spread across Los Angeles County to reach hundreds of thousands of commuters on Metro's sprawling network of bus and rail lines.

Beacons, which are smaller than a deck of cards, use Bluetooth to sense when smartphones are nearby and work through apps already installed on the phones. Major retailers, including American Eagle and Safeway, have tried the micro-location technology. It's also used in more than 20 baseball stadiums, including Dodger Stadium, where a Major League Baseball app offers discounts on Dodger Dogs and guides fans to their seats.

The rapid growth of messaging beacons across the United States has sparked concern among some data and privacy advocates. They warn that the devices could make it possible for companies to flood users' phones with sales pitches. They also complain that the spread of technology is outpacing regulations governing its installation and use.

Metro officials emphasize that cellphone users would have to agree to receive messages.

The technology would allow Metro to target Union Station visitors with precision. The agency could track commuters' travel patterns through Union Station. If someone were heading toward the subway entrances, for example, a message could appear with directions to the nearest ticket-vending machine. Disabled passengers could receive directions to a working elevator.

Alerts could also appear from Metro vendors, such as Starbucks, offering a discount on a cup of coffee at a nearby kiosk, said Lan-Chi Lam, Metro's director of Web and mobile communications.

"But we always want to stay core to our service as a transit agency," Lam said.

The beacons themselves do not store any data on users, she said.

The program could be expanded beyond Union Station. Overall, about 57% of Metro bus and rail riders have smartphones.

In June, the company that manages advertising on Los Angeles bus benches installed beacons at 275 stops. The beacons haven't been activated, and city officials are still reviewing which apps would be allowed to access the systems, according to the Bureau of Street Services.

The beacons should be operating later this year, and more could be added to the city's nearly 6,000 bus benches. Eventually, the system could reach "virtually every nook and cranny of the city," said Randy Smith, chief executive officer with Martin Outdoor Media, the city's bus bench ad vendor.

The first app to connect with the beacons would provide public service messages, such as the wait time for the next bus or simple means to report potholes and other problems, officials said. Smith said several commercial apps also are ready to launch.

Officials with Gimbal, the San Diego company that provided the bus bench beacons, said it was too early to indicate which apps were being developed for the beacons or when they would go live. Kevin Hunter, the firm's chief operating officer, said the city and Gimbal will control which agencies and companies can use the system. "It's not a free-for-all, and developers can't leverage this at will," he said.

Last year, after BuzzFeed reported that hundreds of Gimbal beacons had been installed in New York City phone booths without the public's knowledge, Mayor Bill de Blasio said they would be removed. "That was just a pilot program, to see what could be done," Hunter said.

In November, American Airlines installed 77 beacons in terminals 4 to 6 and LAX's Tom Bradley International Terminal. Frequent fliers who have downloaded the airline's app can receive directions to their gates.

"We're participating with them so we can decide how best to do this," said Dominic Nessi, chief information officer for Los Angeles World Airports. If other entities express interest, he said, LAWA will develop a policy that allows multiple companies to use the same beacons, to prevent "everybody from slapping them up on the wall."

One of the more advanced local uses of the systems can be seen at the L.A. County Museum of Art. Last year, Gimbal donated beacons that allow the museum's app to send guests up to 10 notifications per visit. Some alerts link to information on new exhibits or special audio tours. One explains a famous Jesús Rafael Soto sculpture that resembles dangling spaghetti noodles to people sitting at the cafe nearby.

Metro has yet to set a date for the Union Station system to be turned on.

(Credit: Web)