Everyone knows your location: tracking myself down through in-app ads • Hacker News Board

Re: Everyone knows your location: tracking myself down through in-app ads

#21

Post by gruez » Sun, Feb 02, 2025, 5:39 PM UTC

>If it was LTE, I bet the lat/lon would be much more precise.

False. Apps don't have access to cellid information unless they also have location permissions, in which case they can just request your location directly.

>the free apps you install and use collect your precise location with timestamp [...]

This is alarmist and contradictory given that the author admits a few paragraphs up that the "location shared was not very precise". It might be possible for the app to request precise location via location services, but the app doesn't request such permissions (at least on android, you can't check for requested permissions on iOS without installing the app and running it), so such apps are most definitely limited to "not very precise" locations.

>At the same time, there is so much data in the requests that I'd expect ad exchanges to find some loophole ID that would allow cross-app tracking without the need for IDFA.

At least in theory they're not supposed to do that, but it'd be hard to enforce.

"If a user resets the Advertising Identifier, then You agree not to combine, correlate, link or otherwise associate, either directly or indirectly, the prior Advertising Identifier and any derived information with the reset Advertising Identifier. "

https://developer.apple.com/support/terms/apple-developer-pr...

Re: Everyone knows your location: tracking myself down through in-app ads

#22

Post by gruez » Sun, Feb 02, 2025, 5:43 PM UTC

andrewfromx wrote: post #9

inahga wrote: post #6

There are quite a few interesting tracking flows out there. My rent is paid through a company called Bilt. I discovered that when I shop at Walgreens now, Bilt sends me an email containing the full receipt of what I bought like so: > Hey [inahga], > > You shopped at Walgreens on 12/1/24 and earned Bilt Points with your > Neighborhood Pharmacy benefit. > > Items eligible for rewards > TOSTITOS HINT OF LIME RSTC 11OZ >…

"Bilt Members can earn points on Walgreens purchases made using any card linked to their Bilt account." https://support.biltrewards.com/hc/en-us/articles/2901187842... There's that FSA/HSA benefit section at the bottom which explicitly states that Bilt receives item-level data: https://www.biltrewards.com/terms/walgreens

That just sounds like a standard cross-merchant loyalty program? I don't think there are many examples in the US, but once you realize it's a loyalty program you really shouldn't be surprised that they're tracking your purchase history. That's basically the entire premise.

Re: Everyone knows your location: tracking myself down through in-app ads

#23

Post by dylan604 » Sun, Feb 02, 2025, 5:43 PM UTC

RajT88 wrote: post #17

dylan604 wrote: post #7

Earlier quoted context omitted.

Ugh. Eye roll on the whole “make the world better”. So few SV products remotely make the world better. The purpose of the vast majority is to make money at all costs. I also disagree with what most people claim is making the world better. All in all, I think social media is a net negative for the world for any good that might be found. Every SV thing after that is just chasing the recketship to the moon dream.

I believe this was parodied multiple times in season 1 of Silicon Valley.

That scene in the pilot with the way over enthusiastic founder on stage with Kid Rock was pretty much when I knew I would <3 that show

Re: Everyone knows your location: tracking myself down through in-app ads

#24

Post by gruez » Sun, Feb 02, 2025, 5:46 PM UTC

Yeul wrote: post #3

I read an interesting newspaper article about how the police confiscated a hired gun's iPhone and found that he ran a search on the city his victim lived in. It is these little digital breadcrumbs that makes life easy for the prosecution. Seriously if you are going to do illegal things never ever buy a smartphone.

>the police confiscated a hired gun's iPhone and found that he ran a search on the city his victim lived in.

It's far more likely they just looked at his browser history rather than doing some skullduggery with databrokers or whatever.

Re: Everyone knows your location: tracking myself down through in-app ads

#25

Post by dylan604 » Sun, Feb 02, 2025, 5:46 PM UTC

unification_fan wrote: post #13

dylan604 wrote: post #7

Earlier quoted context omitted.

Ugh. Eye roll on the whole “make the world better”. So few SV products remotely make the world better. The purpose of the vast majority is to make money at all costs. I also disagree with what most people claim is making the world better. All in all, I think social media is a net negative for the world for any good that might be found. Every SV thing after that is just chasing the recketship to the moon dream.

> So few SV products remotely make the world better Because devs have to eat in order to survive?

Right, because SV is epitomized for the struggling dev as much as Haight Ashbury is known for struggling artists.

Re: Everyone knows your location: tracking myself down through in-app ads

#26

Post by inetknght » Sun, Feb 02, 2025, 5:48 PM UTC

inahga wrote: post #6

There are quite a few interesting tracking flows out there. My rent is paid through a company called Bilt. I discovered that when I shop at Walgreens now, Bilt sends me an email containing the full receipt of what I bought like so: > Hey [inahga], > > You shopped at Walgreens on 12/1/24 and earned Bilt Points with your > Neighborhood Pharmacy benefit. > > Items eligible for rewards > TOSTITOS HINT OF LIME RSTC 11OZ >…

> just use cash/certified check from now on

You might want to discover about sophistication and pervasive facial recognition technology used by major retailers. Paid by cash? It can still be tracked to you. For "fraud prevention", of course.

Re: Everyone knows your location: tracking myself down through in-app ads

#27

Post by curiousthought » Sun, Feb 02, 2025, 5:48 PM UTC

inahga wrote: post #6

There are quite a few interesting tracking flows out there. My rent is paid through a company called Bilt. I discovered that when I shop at Walgreens now, Bilt sends me an email containing the full receipt of what I bought like so: > Hey [inahga], > > You shopped at Walgreens on 12/1/24 and earned Bilt Points with your > Neighborhood Pharmacy benefit. > > Items eligible for rewards > TOSTITOS HINT OF LIME RSTC 11OZ >…

This is called Level 3 data, and any merchant can choose to provide it for a reduction in the transaction fees they pay.

Here's a small comment thread from a few months back: https://news.ycombinator.com/item?id=41213632

Re: Everyone knows your location: tracking myself down through in-app ads

#28

Post by nicbou » Sun, Feb 02, 2025, 5:51 PM UTC

inahga wrote: post #6

There are quite a few interesting tracking flows out there. My rent is paid through a company called Bilt. I discovered that when I shop at Walgreens now, Bilt sends me an email containing the full receipt of what I bought like so: > Hey [inahga], > > You shopped at Walgreens on 12/1/24 and earned Bilt Points with your > Neighborhood Pharmacy benefit. > > Items eligible for rewards > TOSTITOS HINT OF LIME RSTC 11OZ >…

Things like that are on my mind when HN rants about GDPR. Something like this would be wildly illegal where I live.

Re: Everyone knows your location: tracking myself down through in-app ads

#29

Post by mistrial9 » Sun, Feb 02, 2025, 5:51 PM UTC

gruez wrote: post #22

andrewfromx wrote: post #9

Earlier quoted context omitted.

"Bilt Members can earn points on Walgreens purchases made using any card linked to their Bilt account." https://support.biltrewards.com/hc/en-us/articles/2901187842... There's that FSA/HSA benefit section at the bottom which explicitly states that Bilt receives item-level data: https://www.biltrewards.com/terms/walgreens

That just sounds like a standard cross-merchant loyalty program? I don't think there are many examples in the US, but once you realize it's a loyalty program you really shouldn't be surprised that they're tracking your purchase history. That's basically the entire premise.

> it's a loyalty program

calling something loyalty does not make it "loyalty" ..

Re: Everyone knows your location: tracking myself down through in-app ads

#30

Post by jmward01 » Sun, Feb 02, 2025, 5:51 PM UTC

A long time ago I had the idea to create an 'accountability server'. The high level idea was for it to generate unique credentials so that you could track to the source who sold your info. There are some ways to do that now, but I wonder if it is time to start exploring that idea again. If you exposed it as a VPN/proxy+app that ran on a server in your home, so that you could collect your own data and provide unique credentials on account creation, then I wonder how much that combination could figure out. Since it could act as a man in the middle it potentially could annotate credential source and see the ads and potentially track them to source. "This male enhancement pill ad is linked to your tire purchase." There is a lot of hand waving here, but I wonder if something like this could be built. The first step to stopping things like this is showing people who did it to them.