[afavour]

> Meanwhile Google has access to all this data

I’m loathe the defend Google but I don’t think this is the case. The replacement for user agent sniffing (client hints? I forget) is a universal thing and I don’t think Google has a secret back door tracking mechanism their ad network is able to use. It would certainly be a big story if they did.

[riku_iki]

> I don’t think Google has a secret back door tracking mechanism their ad network is able to use.

they have 80% population using search, youtube, storing browsing history etc while logged into google account, so they have lots of data about most of the people.

[afavour]

Right but that’s not a secret back door tracking mechanism. It’s a pretty blatant one!

My point is that even this blatant logged in user tracking won’t be able to use user agent strings to track either.

[riku_iki]

yeah, no need some secret backdoor..

[asddubs]

you're the one who introduced the concept of it being secret, your quote just said they have access

[afavour]

> you're the one who introduced the concept of it being secret

There is no publicly known method by which Google’s ad network is able to siphon extra data from Chrome users for targeting etc. If there is one, as OP’s friend suggested, definitionally it must be secret.

[rhaway84773]

Google’s ad network might not have access. But does Google have access?

Because there are many ways Google can leverage this data without giving their ad network access.

Privacy isn’t just about privacy from ads. There are all sorts of non ad related privacy abuses that can exist.

[foobarian]

A while ago now I booked a room on Expedia, which ended in me getting a confirmation email with an itinerary to my Gmail backed address. Lo and behold, few minutes later a CTA pops up on my Android phone offering to create a matching trip in Google's trip planning product. I'm sure it's all above board once you got into the fine print but it was not a pleasant experience.

[notatoad]

yes, client hints.

google "has access to all this data" in exactly the same way any other website does. you request the information you need from the client, and the client can choose to provide it or not. clients provide it by default.

hate on google all you want, but UA reduction is objectively a good thing. "my friend jacob wants to slurp up everything from the user-agent string on the first request" is not a good argument.

[jacquesm]

You only need a backdoor if you do not also have a 6 lane highway to your users premises.

[hotstickyballs]

> I don’t think Google has a secret back door tracking mechanism their ad network is able to use. It would certainly be a big story if they did.

Like Chrome??