In late 2013, Google was reported to be working on a new form of user-tracking device that might replace cookies, the little bits of software that record your web browsing history and provide that information as targeting data to advertisers.
This week we spotted the new system, “Advertising ID,” in the wild. We know it’s being used to track users with newer versions of Android phones. We believe it is running on KitKat, the latest version of Android. Below, we’ll show you how to locate Advertising ID in your settings and turn it off or on.
Its appearance suggests that Android users’ mobile phone use is now trackable with both traditional web cookies in the Android Chrome browser and Google’s new Advertising ID.
What we don’t know is exactly how it works, or what it is tracking. But given that it’s intended to provide usage data for advertisers, it’s a reasonable assumption that it’s recording your web browsing and possibly your app usage too. One possible difference is that Advertising ID may be tracking your phone specifically, whereas cookies track your behaviour. Here are its terms of service for app developers.
Here’s how to locate and change your Advertising ID settings:
On phones running newer versions of Android, you’ll see this new app icon for Google Settings. Open it.
In the next menu, tap Ads …
You can use any of these settings to change how you want to be tracked, or whether you want to be tracked at all.
Here is what we think this all means. (We’re guessing, of course.)
The first line showing a meaningless string of letters and numbers appears to be a “hashed” ID. Most of the time in online advertising, software takes your actual information and “hashes” it into anonymous random information that doesn’t identify you specifically. It merely says, “here’s an Android user with the following characteristics.”
You can reset the Advertising ID. That seems to be a bit like clearing out your cookies from a web browser. You’re still being tracked, but only your new activity is registering.
The “opt out” section could refer to cookies or Advertising ID or both.
“Ads settings” gives you a bunch more options to choose from.
One obvious takeaway — this looks a lot like Apple’s Identifier for advertisers (IFAD or IFA), which also tracks individual phones with a random ID that can be switched off or changed over time.