SilverPush Says It’s Using “Audio Beacons” For An Unusual Approach To Cross-Device Ad Targeting

A number of companies are trying to help advertisers bridge the gap between devices — i.e. to identify when the same person is accessing the web or apps from the desktop, phone and tablets. Now a mobile advertising startup called SilverPush says it has created the most accurate approach yet.

Making those connections is particularly important for advertisers because of the lack of cookies for tracking user behavior on mobile. As a point of comparison, Kleiner Perkins- and Sequoia-backed Drawbridge says it examines behavior on multiple devices and uses statistical models to suggest when multiple devices are being used by one person. (The company recently expanded into video ads.)

SilverPush‘s approach, as explained to me by co-founder and CEO Hitesh Chawla, sounds both simpler and more complicated.

Basically, the company says it uses “ultrasonic inaudible sounds.” If you’re browsing the web and encounter a SilverPush advertiser, then at the same time that they’re dropping a cookie on your computer, they also play one of those sounds. You won’t be able to hear it, but if you’ve installed any app that uses the SilverPush software development kit, it will actually be listening for that sound in the background, and when it detects an “audio beacon,” it’s able to identify that your desktop/laptop computer and your phone/tablet belong to the same person.

I pointed out that this could be pretty creepy, since it sounds like there’s an app listening in the background on your phone or tablet. Chawla acknowledged that there’s a risk of negative public perception, but he said that SilverPush isn’t receiving any actual audio data — once a match has been made, the only thing that gets sent back to the company is the identification code linking the devices. Chawla also said he’s working with the Mobile Marketing Association to develop guidelines around using this technology in a way that respects users’ privacy.

I also asked if there are potential obstacles to making a match. For example, my loud apartment air conditioner was blaring during the call, so I wondered if that might interfere. Chawla responded that noise shouldn’t be an issue. The biggest obstacle, he said, is distance; it won’t work if the devices are too far away.

He added that some SilverPush advertisers (including Procter & Gamble and messaging app Line) are already using these capabilities, as are “a few” mobile publishers (mostly game developers). It works on both iOS and Android and could potentially be used in TV ads, too.

SilverPush announced earlier this year that it had raised $1.5 million from IDG Ventures, 500 Startups and others.