Facebook Is Testing a Feature That Can Track Customers' Physical Movements at Businesses The social network encourages users to check in for free Wi-Fi, but the routers can monitor your movements.

Facebook has quietly been testing a new feature to help brick-and-mortar businesses engage with customers on their smartphones and give them more insight into customer habits. The idea: encourage users to check in on Facebook in exchange for access to free in-store Wi-Fi.

According to the Facebook Help Center, smartphone users who connect to a network that has Facebook Wi-Fi activated will be automatically redirected to the business' Facebook page. Then they are prompted to leave a message to let their friends know where they are and what they're doing. Customers can elect not to check in and still use the complimentary internet connection.

But business owners get more than just a social check-in. The new feature only works if merchants have a Meraki wireless router with a free feature called Presence. The routers then collect information from nearby smart devices, giving business owners "location-based performance indicators including capture rate, median visit length, repeat visit rate, total number of visitors, and total visits for a given site," the company says.

Meanwhile, Facebook can collect data on users based on their check-ins, such as where users go, when and how frequently.

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Meraki, a cloud network company acquired by Cisco Systems last year for $1.2 billion, touts Presence as a seamless way to increase brand exposure while also collecting data about mobile behavior across locations to "enhance your onsite customer experience."

So while customers enjoy free internet access, business owners can ratchet up social interactions and collect tangible metrics on the habits of their customers, enabling them to predict behavior and market more effectively.

There hasn't been an official announcement of the project from Facebook. An iteration of Facebook Wi-Fi has been in use only at a small handful of businesses in the San Francisco Bay area, Meraki says.

Facebook isn't the only company that has experimented with tracking customers over Wi-Fi. Earlier this year, Nordstrom concluded a test for which it used Wi-Fi signals to track the movement of shoppers in its retail stores, though it said the information it collected was anonymous.

While collecting this type of information can be valuable to business owners, if the collective outcry over the NSA's data-mining efforts is any indicator then customers may have a negative knee-jerk reaction to having their movements tracked and recorded every time they go to a coffee shop or pass through a hotel lobby.

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