Google is busy rolling out a new kind of web tracking cookie to give the company an even deeper insight into individual online browsing habits. So what’s so special about how this cookie crumbles?

“Google is introducing a way to track you on your mobile apps,” says Will Oremus of Slate.

The company is already adept at tracking users on the open web, but more and more web browsing is done through apps on their phone, which are not subject to Google’s web tracking cookies. This makes it harder for it to deploy targeted advertisements.

With this new technology, Google is trying to is link the cookies on the web with the anonymous trackers that already log activity through apps.