I’ve recently found that when I visited a website of an app I once used, rejected the cookies, that once I left the site I got an email from the company. This has happened twice and is quite disconcerting. It seems the site is knows who I am and then sends me an email.
How do all you clever techo’s deal with this issue?
How long ago did you use the app? Did you have an account of some sort on their website? Any chance they’re able to match your account just by IP address?
In case you don’t know yet, this might be an interesting read:
There are companies (e.g. LeadForensics) that can figure out who you are and associate with contact information. They use some automated methods, but they also spend a lot on humans to connect data, validate/verify etc. I’ve helped implement that particular company for clients (sorry.)
There are some anti-fingerprinting steps you can take with your browser. Good adblock also helps since a lot of these use detectable JS scripts to identify you. If the JS can’t run, all they have is your IP hitting a server, which you can mask with a VPN or Private Relay.
There’s definitely more they can do and track, per Rob’s link, and more you can do, too.
You can also run a fingerprint check from the EFF:
I’ve had the app ages. Maybe it is ip, but mine is a range of ip’s from my host.
What apps or options help minimize this?
“Resistance is futile”, I’m afraid…
(I have experimented with apps and browser extensions, but most made my fingerprint more unique…)
I delete my history every time I finish using a browser. Been doing it as long as I can remember.
Yes, it’s hard. It depends on what you’re worried about avoiding. If you’re worried about ad tracking or governments, I’d say it’s closer to futile to expect to still do everyday browsing from a personal computer. If you just don’t want your email/phone to be associated with your visit in a way that is going to actually result in them contacting you, AdBlock and switching IP addresses (private relay/VPNs) should be good enough.
I tried the coveryourtracks site. It said that I had strong tracking protection. Probably the best I can do.
This crosses into the same territory as our discussion of the Loupe app.
There’s a certain degree of stuff that your browser “leaks” because it pretty much has to. There’s another category of stuff that your browser “leaks” because the average user (a) expects websites to function, and (b) doesn’t want to be prompted about dozens of things every time they load a page.
And when you combine those things, toss in centralized companies that aggregate data, and throw in AI analytics, it’s possible to make deductions.
Sometimes those deductions are wrong. My wife and I, out of nowhere one day, started getting TONS of ads in Spanish. I’m guessing that our fingerprint was confusingly similar to somebody else in the same geographic region, and we got inadvertently targeted.
But when those deductions are correct, it’s creepy as heck.
Also, related, you don’t actually have to SUBMIT data on a website for them to capture it. Any JavaScript capable of autofilling a field (like an Amazon search bar) is just as capable of grabbing your info before you click “submit.”
So if you type “beanie babies” into Amazon, but thnk better of it before you submit the form, it’s completely plausible that you’ll be stalked by beanie babies ads for the next few days. 
The best defense against tracking I’ve found is enabling Wipr’s Filtr blocker.
Aside from this any website can use fingerprinting, same with most web apps. Native apps block it as they are not running in a form of web framework.
You can use digital self-defense. Here are some very good tools (some require a few weekends to get up to speed, others just one hour):
There are many macOS users in this community; macOS is significantly better than Windows when it comes to privacy. However, Linux would be the best option (preferably an atomic distro).
All my purchases are tracked by my credit card companies, and the ones I do in person also includes the location where they occurred. Add that to the automated license plate readers, ring door bells, and the iPhone in my pocket and the authorities, etc. wouldn’t have a problem reconstructing my daily activities. Even Amazon allows advertisers to target people by their “demographic, location, interests and previous purchases,”
Considering how much data I produce each day just living my life, I wonder if anything significant is added to what is known about me, from my internet traffic?
I’d say your Internet traffic adds another dimension to what they know about you, provided they can tie it to the other information.
Let’s say they know you visited three tire websites yesterday. You’re probably researching tires to make a purchase. If they know that you’re online identifier 12345, that’s aggregate data. They can tell that this guy who needs tires owns a Mac computer, and lives in a particular city/state/etc.
But if they can tie that identifier 12345 to you, then your local Walmart could conceivably send you an ad/coupon/whatever to try to get you to purchase tires. And the advertisers can charge WalMart for that privilege.
There are obviously much darker uses for that information as well. We’re reaching the stage where a digital version of “Minority Report” is increasingly possible.
A new MacBook Neo after every browsing session. 
So we’re basically saying, turn off your computer, get off your butt, visit the shop and pay in cash and leave your smartphone at home for the entire process?!
I have a vague recollection of a life like that 
The only way to be completely secure is to wrap your computer in tin foil!