Looking at my dashboard now I can see data on language, browser, mobile model, referral, etc. I think some are just not present in the mobile version of analytics, but I can't see what data this would not be collecting.
> However a lot of GA's stalking behaviour relies on having cookies on a specific Google-controlled domain
This also reminds me that this simple technique can bypass 3rd party cookies rules.
> author's nefarious goal.
You clearly misunderstood my goal.
You proxy cookie for party3.com
I proxy cookie for party3.com
But there isn’t a good way for me, you or party3.com to correlate these cookies unless we have some agreed out-of-cookie-band way to do so.
I’m sure those will come up, but they will be well known and likely easy to block once they are.
A proxy can send whatever cookie it wants to the server (a proxy can actually hide the fact it's a proxy and make itself look like a normal client).
However a lot of GA's stalking behaviour relies on having cookies on a specific Google-controlled domain. The proxy using a different domain means it won't be able to neither access nor set those cookies. Good for privacy but obviously (and thankfully) bad for the author's nefarious goal.