You can measure conversions without relying on personally identifiable information. Adding e.g. a non-personal tag to your URL will enable you to track the source of a conversion. If this happens in a browser you can even store that (non-personal) information in the localStorage or a cookie, so even if the user doesn't convert immediately and only comes back after e.g. a week you will be able to tie the conversion to the specific ad. Where in that process do you need personally identifiable information?

Also, Facebook doesn't only use these identifiers for conversion tracking, it uses them to create a persistent profile of a person that often ends up containing a ton of sensitive information. Believe it or not, a lot can be inferred about you from your app downloads and website visits. As of now FB was mostly able to perform this kind of tracking without the user really knowing, the only thing Apple does here is drag this practice into the open and give users a real choice.

In my opinion a privacy-first OS should inhibit any kind of cross-app / cross-device personal tracking, I predict this will happen in the next 5-10 years, for now it seems to be too extreme still.

I never said personally identify, just uniquely. The IDFA, the thing surrounding all of this drama, does exactly what you describe.

Well, a unique identifier that is tied to a specific device is considered personal information.

Even if you can change it at will?

Yes, even then. If that wasn't the case it would be trivial to circumvent the GDPR, as then basically any pseudonymous data would be considered non-personal. A Google Analytics user ID is also random and can be changed at any time, still the data that Google collects is considered personal.

We aren’t discussing the collection of user data here. The IDFA ad system does not require anything more to function as described.

While in practice some user data is used to make a hash to increase the conversion accuracy, it’s by no means necessary.

> You can measure conversions without relying on personally identifiable information. Adding e.g. a non-personal tag to your URL will enable you to track the source of a conversion

That literally is what we're talking about

> Imagine for a moment that you want to advertise your new iPhone app on Facebook.

i don't think that's what you're describing here.

> It’s important to know if someone clicks an ad and downloads your app. That’s called a Conversion. It’s used to measure the effectiveness of the ad campaign and the value you gain from spending money on an ad.

i think you've conflated A/B testing with user-profiling. you will obviously know if a campaign has been "effective", if sales increase. you absolutely do not need to uniquely identify a user to do this (which is what happens today).

> That’s unique ID is what Apple wants to remove,

as stated, apple don't want to remove it, merely make it opt-in. and if the end user isn't opting in, they probably don't want it.

> you will obviously know if a campaign has been "effective", if sales increase.

This is simplifying marketing too much. You’re likely to run concurrent campaigns on different platform, Facebook, Instagram, Google Search, Twitter, etc.

Marketers would like to understand what campaigns and what medium helps drive sales/installs. No need to waste money on Twitter ads if it turns out no one actually ends up buying.

This is easily managed by changing the url based on the source of traffic (e.g., the omnipresent ?camId=foo on so many links). Heck, back when I published a magazine, I did this in analog form by using slightly different addresses for mailed in subscriptions (adding a Dept S to the address for the ad in Step by Step, Dept H for How Magazine). It doesn't take intrusive user tracking to be able to measure this sort of thing.

There are no URLs in app installs. The ad links to the iOS app store, and Apple does not give you any information post install on where the source came from.

Most ads don't link directly to the app store, but instead send you through a tracker site which logs the click before forwarding you to the app store.

As I understand it there would still be a unique identifier related to the specific campaign.

If I put an ad in a newspaper, or a commercial on TV, and this ad results in a customer purchasing my product, they don't give me a 'unique ID' for the ad that triggered their purchase. Hell, the ads aren't even targeted to a specific user, only to the audience of a paper or TV network.

Yet, when I open a paper or turn on the TV, there are plenty of paid advertisements. Why would the web need to be any different ?

Don't charge for clicks, just charge for showing the ad. Don't target ads based on personal data collected from users, target them based on the content of the page they're shown on. You know, just like TV and print ads have always done.

...because paper and TV advertising is dying, largely because it is horribly ineffective for the reasons you described.

And yet we're all buying diamonds and slathering on deodorant...

[1] https://www.smithsonianmag.com/history/how-advertisers-convi...

Looks like Facebook agrees with you:

"The social media giant rolled out full-page ads across popular publishing houses such as the New York Times, Wall Street Journal, Washington Post, and more..."

There seems to be a certain irony in this.

The cable company and newspaper would absolutely love to do that if it were possible on their technology.

If you put an ad on TV, the cable company is wasting valuable time showing your ad to a ton of people who will never purchase your product (I wonder how many hours of my childhood was spent in front of things like diabetes ads, funeral home ads, depression medication ads). Same goes for newspapers.

If they could somehow target ads based on who's watching, the ads would be massively more effective and they could charge a lot more for showing ads.

By targeting ads and charging so much more for ad time, some companies can even afford to offer their services for free, which massively increases the audience, which brings in more money, which gives them the budget to build a bigger, better service, which increases their audience, which brings them more money, etc etc

And that's how you end up with Facebook and Google.

Obviously the problem is that this isn't transparent. Many people don't know why they get all of this complex technology for free. It's not explained when you sign up for a new account.

> If they could somehow target ads based on who's watching, the ads would be massively more effective

They already can, and do. They know what the audience of their shows is and schedule the ads accordingly. Don’t show ads for funeral homes during Saturday morning cartoons. Hell, this is how we got the whole concept of a soap opera: soap ads during shows targeted specifically at housewives.

You advertise cars during car shows, tools during DIY shows, toys during cartoons, etc.

There are simple low-tech ways to do this. Differing phone numbers for call-in orders, adding a meaningless suite or department to the address for mail-in orders. Even a slight variation on the URL for web contacts. None of this requires Facebook-style tracking.

Ads that don't give the advertiser direct tracking usually give users a code or url specific to a campaign to track their effectiveness. This is an "if they could do more they would" situation.

Where’s your proof that advertising or tracking conversions even works in the first place?

https://freakonomics.com/podcast/advertising-part-2/

>That’s unique ID is what Apple wants to remove, which breaks the advertising model in entirety.

You say that like it's a bad thing.