Home Mobile Why Starting With Cookies Doesn’t Make Sense For Cross-Device Tracking

Why Starting With Cookies Doesn’t Make Sense For Cross-Device Tracking

SHARE:

Are some marketers approaching cross-device backward?

Tom Laband, CEO and co-founder of mobile data marketplace adsquare, thinks so.

“We see many advertisers start with cookie-derived data and bridge that to mobile IDs using cross-device vendors – and to me, that doesn’t make sense,” Laband said Thursday at a company event in New York City.

Device IDs, like IDFA on iOS and Android’s advertising ID, are persistent and often used as the connective tissue to link customer activity and identifiers across devices and channels.

“These are way more persistent than a cookie ID,” Laband said.

But scale is always an issue, and in order to get there, onboarders and cross-device providers are increasingly turning to probabilistic methods to pump up their reach.

“What’s happening now is that [marketers are] taking a desktop cookie and probabilistically connecting it to a mobile user,” said Kathleen Comer, GM of client services at The Trade Desk.

Even if they’re using a cross-device vendor like Tapad, Drawbridge or Oracle’s Crosswise to make the match between a cookie and device ID, the audience that’s being created is essentially a lookalike audience, rather than a one-to-one match to a device ID.

“I think we need more marketers to start using mobile data for mobile campaigns, as opposed to working with the big cookie-focused DMPs out there with fancy cross-device technology that allows the bridging of cookies to mobile devices,” Laband told AdExchanger.

It also makes sense to start with mobile IDs, he said, because the lifetime value of an app identifier is greater than a cookie – even a persistent cookie, which doesn’t expire when users close their browsers, but is at risk of being cleared at any time.

In other words, Laband argued, a more solid strategy would be to coalesce cookie data around a persistent anonymous identifier tied to a device, rather than creating cookie syncs between tracking data across different digital ad platforms – which can lead to data leakage – and then connecting those matched cookies to a mobile ID.

“When you start with a mobile device, there is no cookie syncing or there is less, and then you can use cross-device technology to bridge to cookies,” Laband said. “A profile can be more granular and be more accurate using a mobile ID, and mobile also has data sets that are not available in the cookie world, like location data and telco data.”

Must Read

Monopoly Man looks on at the DOJ vs. Google ad tech antitrust trial (comic).

2025: The Year Google Lost In Court And Won Anyway

From afar, it looks like Google had a rough year in antitrust court. But zoom in a bit and it becomes clear that the past year went about as well as Google could have hoped for.

Why 2025 Marked The End Of The Data Clean Room Era

A few years ago, “data clean rooms” were all the ad tech trades could talk about. Fast-forward to 2026, and maybe advertisers don’t need to know what a data clean room is after all.

The AI Search Reckoning Is Dismantling Open Web Traffic – And Publishers May Never Recover

Publishers have been losing 20%, 30% and in some cases even as much as 90% of their traffic and revenue over the past year due to the rise of zero-click AI search.

Privacy! Commerce! Connected TV! Read all about it. Subscribe to AdExchanger Newsletters

No Waiting for May – CES Is Where The TV Upfront Season Starts 

If any single event can be considered the jumping-off point for TV upfronts, it’s the Consumer Electronics Showcase (CES), which kicks off this week in Las Vegas, Nevada.

Comic: This Is Our Year

Comic: This Is Our Year

It’s been 15 years since this comic first ran in January 2011, and there’s something both quaint and timeless about it. Here’s to more (and more) transparency in 2026, and happy New Year!

From AI To SPO: The Top 10 AdExchanger Guest Columns Of 2025

The generative AI trend generated endless hot takes this year, but the ad industry also had plenty to say about growing competition between DSPs and SSPs. Here are AdExchanger’s top 10 most popular guest columns of 2025 and why they resonated.