Since it began, Google has kept the vast amount of user data it tracks in silos. Information gathered from users while signed into Google accounts — searches, YouTube videos watched — was kept separate from data on web pages and apps visited.
Not anymore.
The company is rolling out a new service that pools data from across the entire web and mobile devices, giving it a potential boost to its core ads business. The big caveat: It’s giving users total control — and with that, they’ll have carte blanche to block particular ads.
It’s a way for Google to get ahead of the growth in ad-blocking. By building the feature opt-in, it’s also a way for Google to combat criticism of its privacy practices.
Starting today, its billion-plus users will start seeing a notification in Gmail or Chrome about a new privacy update. Therein, Google will offer an option that may look* like this(depending on the device you are using):

With it, Google is rolling out a new site called My Activity, an extension of My Account, the personal privacy user hub it introduced last year. The new site lets you see all your Google activity — your searches, videos, web history, Android activity (if you have one) and so on — and zap certain records from one portal. (You had to do this in multiple places before.)
Google has made a concerted effort to broadcast its data protection policies in the past year. That’s driven, in part, by the frequent derision aimed at Google — largely coming from Apple — for its reliance on collecting massive amounts of data.
Facebook, Google’s chief rival for ad dollars, has unfurled similar tools for selling ads across the web, although the social company built its feature with a different default — users had to opt out.
Google’s new data tracking does not immediately change the way it sells ads, according to a source familiar with the company. (For instance, Google still does not target you with desktop display ads based on searches.)
But it opens up tweaks to ad selling in the future. Digital advertisers have long clamored for solutions that can track customers from their desktop browsers to their phones and back. Google is finally setting the stage for that.







