Skip to main content

Advertisers are using inaudible noise to figure out what devices are yours

Online Privacy
Image used with permission by copyright holder
Advertisers love browser cookies for their ability to determine what sort of ad a user will want to see, as well as provide all sorts of useful information about how the device is used. The problem with cookies, from an advertising standpoint, is they only have data on one device at any given time, and in the course of a day you might use a smartphone, tablet, a computer, a smart TV, and a gaming console. Now, it appears that inaudible sounds are being used to track users across all of their devices, according to a report from Ars Technica.

The technology involves the use of ultrasonic noises that can’t be picked out by human ears, but can be detected by devices with a microphone. Advertisers can embed the noises into any ad with an audio component, including those shown on TV. This makes it possible to not just track devices, but also track devices that users normally don’t think susceptible to such invasions of privacy.

The most prominent company running this software is SilverPush, which works by embedding the software into other popular applications. Without a user even knowing that it’s running, SilverPush listens for the ultrasonic codes that ads and other applications broadcast.

“When a user encounters a SilverPush advertiser on the web, the advertiser drops a cookie on the computer while also playing an ultrasonic audio through the use of the speakers on the computer or device,” states the report. It goes on to say the sounds allow an app “to know which ads the user saw, how long the user watched the ad before changing the channel, which kind of smart devices the individual uses, along with other information that adds to the profile of each user that is linked across devices.”

SilverPush doesn’t list the names of the apps or developers that include the tracking software, but according to the same CDT report “As of April of 2015, SilverPush’s software is used by 67 apps and the company monitors 18 million smartphones.” That’ a substantial number, and it’s not the only company using this sort of software for cross device tracking.

The privacy implications are obvious, especially considering there’s little way of knowing what apps might include software from SilverPush or one of the other companies like Drawbridge and Flurry. That also means there’s basically no way to opt out of this sort of tracking, although ensuring your microphone and speaker privileges on your smartphone are managed correctly.

Editors' Recommendations

Brad Bourque
Former Digital Trends Contributor
Brad Bourque is a native Portlander, devout nerd, and craft beer enthusiast. He studied creative writing at Willamette…
Social media sites can predict your behavior even if you don’t use them
twitter q1 2018 report on mobile phone new

Bad news for people who are trying to preserve their privacy by staying off social media -- a new study has found that your privacy is at risk even if you are not personally using social media sites. The findings of researchers from the University of Vermont show that "privacy on social media is like second-hand smoke. It's controlled by the people around you."

Using data gathered from nearly 14,000 Twitter users, the team of scientists analyzed information about the content of people's tweets. They found that using information from the tweets of a few of someone's contacts -- just eight or nine friends -- made it possible to predict that person's tweets as accurately as using data from their own Twitter feed. This means that it's possible to predict your Twitter content from seeing your friends' tweets, even without having access to your Twitter.

Read more
How to use Your Phone app to transfer photos, send texts from your Android device
Microsoft Your Phone app

Do you ever email yourself a photo or screenshot to get it from your phone to your computer? Maybe you upload pictures to a service like Google Photos or Dropbox and then download them onto your PC. With Microsoft's Your Phone app, you can link your Android phone to your Windows PC or laptop directly and simply drag and drop photos or screenshots. The app also allows you to receive and send text messages from your phone on your computer. We'll show you how to set it up, what it can do, and where it falls short in this guide.
How to set up Microsoft's Your Phone
If you have a PC or laptop running Windows 10 April 2018 Update (Version 1803) or later, and an Android phone running Android 7.0 Nougat or later, then you can use Microsoft's Your Phone. Both devices must be connected to the same Wi-Fi network.

Note: Support for iOS is supposed to be coming, but there's no sign of it yet at the time of writing this guide. 

Read more
Best router deals: Save on mesh networks and Wi-Fi 6 routers
The Netgear Nighthawk AXE11000 Tri-Band Wi-Fi 6E Router on a table.

Strangely enough, routers have had a huge technological bump in the last few years due to the number of devices that need to be connected to the internet. That's one of the main aspects of the new Wi-Fi 6, a standard that not only increases speeds and quality of the connection but addresses the issue with ten devices or more needing to connect to the internet constantly without impacting quality. To that end, if you haven't upgraded your router or mesh network in three to five or more years but are increasingly buying more smart-home products, grabbing a modern router with the latest technology is probably a good idea.

Best Router Deals

Read more