Amazon faces a privacy backlash for its Sidewalk feature, which turns Alexa devices into neighborhood WiFi networks that owners have to opt out of

• Amazon Sidewalk is launching in the US as an opt-out feature that will connect Echo and Ring doorbells to any nearby Alexa device, even those owned by your neighbors. 
• Amazon said Sidewalk uses WiFi from neighbors to create "a shared network that helps devices work better," but some raised privacy concerns. 
• Amazon apologized to UK Alexa owners, some of whom were notified of the US-only launch. 
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Amazon users are being automatically opted into Sidewalk, a feature that will connect Alexa devices to nearby WiFi networks, even those owned by someone else. 

Sidewalk uses Alexa devices, including Echo and Ring video doorbells, to create a "shared network" that will help "devices work better," Amazon said in an email to device owners. It allows nearby devices to use a portion of a neighbor's WiFi bandwidth, so that devices can have more range. 

Amazon said on a launch page: "These Bridge devices share a small portion of your internet bandwidth which is pooled together to provide these services to you and your neighbors. And when more neighbors participate, the network becomes even stronger."

Anticipating privacy concerns, Amazon published a research paper detailing the technology behind Sidewalk and the steps taken to keep users' data private. The company concluded that privacy was one of the "foundational principals" of Sidewalk's design. 

The report's authors said: "By sharing a small portion of their home network bandwidth, neighbors give a little – but get a lot in return." 

Some were still skeptical of whether such a network would keep user data private. Surrey University Professor Alan Woodward, who specializes in cybersecurity, told BBC News that Sidewalk should be an opt-in feature, adding, "It feels wrong not knowing what your device is connected to."

Ian Thornton-Trump, chief information security officer at Cyjax, told Forbes the launch was "deeply problematic from a privacy perspective."

"The 'on by default' approach is not consumer friendly. 'No one rides on my Wi-fi for free,' especially a giant corporation with billions of dollars," Thornton-Trump said.

In an emailed statement, an Amazon spokesperson confirmed that Sidewalk is automatically enabled for existing customers.

The spokesperson said: "But well before Sidewalk launches, we will notify existing customers with eligible Bridge devices so they can consider the benefits of Sidewalk before deciding if they want to change their preferences. After all existing customers are notified, all customers setting up a Sidewalk Bridge for the first time will have the opportunity to enable Sidewalk during device setup. All customers will have the option to change their Sidewalk preferences anytime in their Alexa app or Ring Control Center settings."

As of Wednesday, Amazon was only rolling Sidewalk out in the US, but some UK users reported getting an email about its launch. 

—Amazon Help (@AmazonHelp) November 25, 2020

Amazon apologized on Twitter via its Support account, saying: "I apologize for any confusion. We recently began emailing customers with Echo devices registered in the US to give them more information about Amazon Sidewalk. This service will only be available in the US when it launches."