Last week, Google announced a new smart home device: a smart display that features a 10-inch screen, camera, and speaker. The speaker has a privacy feature that relatively few electronics do these days–a hardware kill switch, which physically disconnects both the device’s camera and its microphone so there’s no way that Google can listen in on your conversations. Unless, of course, you want it to.
This hardware switch, which looks like an elegant version of your average light switch, is part of a growing trend of providing users with a physical way to disable a product’s sensors. Amid a steady series of data breaches and privacy scandals, tech companies like Google, Apple, and Amazon are attempting to address users’ concerns through this simple feature. Unlike software settings, which users have to dig through to prevent companies from collecting reams of personal data like them, the hardware kill switch is a simple, tactile way to give people the assurance that corporations can’t listen in on your private life.
Kill switches aren’t a perfect solution to the problems of privacy in 2019–for starters, because they, by definition, make devices unusable. And as Larry Sanger, the cofounder of Wikipedia and the chief information officer of the blockchain-based wiki Everipedia, pointed in a recent blog post, kill switches are still far from commonplace, particularly in mobile phones where it may be most important.
Still, the list of companies designing hardware switches into their devices is growing, though it’s mostly concentrated within the smart home space. Google’s smart display, the Nest Hub Max, offers a kill switch for its mic and camera, and all its other Google Home products that don’t have cameras–which is all of them, with the exception of Nest security cameras–similarly have a hardware kill switch for their microphones. Google says that Nest Cams do not have hardware switches for security reasons, but that users can turn off any video or audio recording in the Nest app. Amazon says that its family of smart home devices, including the Echo, the Echo Dot, and the Echo Show, also have hardware kill switches to disable microphones, which have always been built into the devices. The trend is slowly coming to laptops and phones as well: In 2018, HP debuted a hardware kill switch for the webcam of its Spectre laptop that disconnects the camera. Apple announced in 2018 that its latest Macbook Air and Macbook Pro would physically disable the microphone when the computers are closed, which isn’t quite a kill switch because you can’t disabled it when the computer is open, but is a gesture in the same direction.
These major electronics makers are catching up to the niche hardware company Purism. Founded in 2014, Purism sells two Linux laptops that have two different switches: one that disables the device’s webcam and microphone and one that cuts power to the Wi-Fi. This fall, Purism will launch a smartphone that adds a switch to take the modem offline completely along with the other two in the company’s laptops, finally bringing hardware kill switches to mobile devices.
For Purism, hardware kill switches are about giving security-conscious users a last line of defense against hackers and malware–in particular, remote access Trojans, which, once installed on a device, give a hacker access to a person’s camera and microphone without their knowledge. But while protection against hackers is one reason for a hardware kill switch to turn off a camera or microphone, they’re becoming a mainstream privacy feature in smart home devices, laptops, and even phones for another good reason.
As a result of a stream of security breaches and privacy scandals from Big Tech companies like Google and Amazon, which have come under public scrutiny from journalists and lawmakers for their opaque data collection practices and privacy violations, consumers are slowly becoming more aware of the amount of data that companies collect on them (even though the Pew Research Center found earlier this year that 74% of people didn’t know that Facebook classifies their interests, which indicates many are still unaware about how corporations’ data practices work). That’s part of the reason why privacy has played a central role in recent marketing campaigns from Apple, Facebook, and most recently Google. Google hasn’t previously emphasized that its smart home products have kill switches, suggesting that highlighting the feature during the Nest Hub Max announcement may be part of the company’s new public focus on privacy.
In 2019, Google announced that users would be able to turn on a microphone hidden inside Google Nest Guard that it hadn’t previously disclosed, surprising users who hadn’t realized there was a mic inside the device. The company later said the mic was never intended to be secret and the omission was a mistake. Bloomberg reported in April that Amazon employees are listening in to whatever you say to Alexa, and CNET found in May that even when users delete their audio recordings from their Amazon account, the company keeps the transcripts (Amazon said this was a bug). In 2017, the New York Times reported that some gaming apps can utilize a phone’s microphone to detect what television shows and advertisements the person is seeing, even if the app isn’t open. Many of us have had the uncanny experience of having a conversation with someone and then seeing an ad that references that conversation not long after (even if it might be pure coincidence and the result of creepily good ad-targeting).
Adding a kill switch is a convenient way for companies to address these scandals through a simple hardware feature. After all, instead of requiring users to dig through a settings page to turn the microphone off–something that Android phone users have to do if they don’t want the Google Assistant to have access to their phone’s mic–the off switch is built right into the hardware.
“You’d need to defy the laws of physics to re-enable [the camera and microphone] with anything other than a switch,” says Ashton Udall, a product manager at Google who oversaw the Nest Hub Max’s development.
The Nest Hub Max’s kill switch looks different from the mute buttons on the original Google Home devices, which the company says are also hardware kill switches. Udall explains that the Nest Hub Max’s kill switch was redesigned to look like an actual switch so that it would be easier for people to understand. When a user flips the switch, an orange light comes on next to the camera to tell them that it has been physically disabled, the speaker tells the user that the camera and mic are off, and the screen indicates the change through camera and mic icons as well–just in case the user wasn’t aware. “The decision was based on how can we make this even more clear for users so they know when it’s engaged and when it’s not,” Udall says.
The simplicity of the switch is a benefit for the laptop maker Purism as well, making it a straightforward design feature to give users more peace of mind that doesn’t require much explanation. “Cutting off power is high-level security, but it’s also really simple,” says Kyle Rankin, the chief security officer at Purism. “Everyone can understand flipping a switch.”
And yet, actually utilizing the kill switch eliminates much of the device’s functionality. As an Echo owner, I rarely use the hardware mute button, even though I care about privacy, because often I forget or it’s just more convenient not to. In that sense, though kill switches offer users an easier way to disable the most invasive parts of technology, it’s not a very practical solution–and it remains to be seen if people will use it regularly. And even if you do utilize it, you’ve still brought a camera and microphone into your home.
That’s the reason why Sanger thinks that anyone who would care that there’s a hardware kill switch would never have a smart home device in the first place. “There’s at least three different categories there you need to worry about: hacking, systematic corporate abuse of the information, like data mining and selling the results, and then there’s the internal hacking or hacking by employees,” he says.
Ultimately, it comes down to trust. Users still have to rely on Google or Amazon’s word to trust that these kill switches are actually built into the hardware (something several people have noted on the developer website Stack Exchange and on Reddit). That’s why Purism publishes images of its computers’ guts so that security-conscious people can see with their own eyes that the company’s switches are hardwired in.
The doubt is understandable. “Everyone has been taken advantage of tech companies for so long, everyone operates from the standpoint of skepticism,” Rankin says.