WWDC 2025: 5 great updates for Apple’s AdAttributionKit, but there’s a catch

As expected, WWDC 2025 brought a few key updates to AdAttributionKit, the new SKAdNetwork. Big picture, AAK is going to be more flexible, more accurate, more useful for understanding geo data on your installs, and easier to test.

Here are the 5 critical updates:

1. Overlapping re-engagement windows
2. Configurable attribution windows
3. Configurable attribution cooldown
4. Country codes in postbacks
5. Easier testing postbacks

What do you need to know? Let’s dive into each, and then we’ll talk about the catch.

1. Overlapping re-engagement windows

Currently, you can only have one re-engagement conversion window. In iOS 18.4 and beyond, you’ll be able to have multiple overlapping conversion windows

Why on earth would you want this?

 

Maybe you’re running multiple re-engagement campaigns. Maybe you’re using multiple re-engagement partners. 

Now you can use a “conversion tag” to keep these re-engagements separate. And now you can know which re-engagement effort was successful.

2. Configurable attribution windows

Currently in AAK you can have a 30-day click-through attribution window or a 1-day view-through attribution window. 

In iOS 18.4 and above, as Apple shared at WWDC 2025, you’ll be able to specify your desired attribution window length. You can do that:

• Per ad network
• Per interaction type (click or view)
• Globally

Interestingly, you can also ignore some interaction types. So you could theoretically ignore all view-through ads from a specific ad network, at least for the purposes of attribution.

Important note: this is only for installs, not re-engagements.

Why?

Because, as Apple says, re-engagement ad interactions and conversions happen right after each other with no time gap in between. 

Now you’ll have more precise control over what gets attributed to your ads: perhaps shorter windows for performance-focused campaigns, and longer for more brand-oriented ads.

3. Configure attribution cooldown

Right now, if conversions in SKAN or AAK happen very quickly, signals can be misattributed. For example: an install and a quick re-engagement.

In 18.4 you’ll be able to configure an attribution cooldown to block subsequent conversions from competing for attribution. You can set that per conversion type (both installs and re-engagements). For example, you might set a 6 hour cooldown for installs, and a 1 hour cooldown for re-engagements.

Here’s how Apple sees it:

After an ad network serves an ad, and the ad-driven conversion happens, the window for advertisers to measure user engagement opens. We refer to this window as the conversion window. Advertisers can measure the value of the conversion based on activities people take in their app, such as subscription and In-App Purchase, by invoking the updateConversionValue API.

In reality, many of these ad attributions might be happening simultaneously for the same advertised app on the same device. And the conversion windows may overlap, in which case, a measurement might not get accorded to the most appropriate conversion.

Configurable attribution cooldowns prevent that, ensuring that the right ad receives credit for valuable post-conversion events.

4. Country codes in postbacks (!!!)

This is huge!

In SKAN and the first versions of AAK, there was no default geo information, meaning that if you wanted it, you needed to spend some conversion values for it … and hope that your ad campaign targeting accurately predicted where all your ads would be seen.

Now postbacks can include an optional country code which is derived from the App Store itself.

While it is subject to crowd anonymity for privacy reasons, assuming you surpass the privacy thresholds, you’ll get geo data by default when this is turned on. This will allow for better geo-targeting, optimization, and campaign analysis.

5. Easier testing postbacks

iOS 18.4 adds a development postbacks tool in Developer Settings which allows you to test your AAK attribution set-up much easier.

With this, you can:

• Generate development postbacks without needing a live publisher app / ad flow
• Manually configure:
  • Conversion type (install or re-engagement)
  • Country code
  • Data granularity
• Send postbacks to your test server
• Update conversion values via API calls during tests
• Manually transmit postbacks or allow them to be sent automatically

This will make it easier to validate your server pipeline, and you won’t need to run a complete ad-to-install flow for testing.

WWDC 2025 summary: new AAK features and benefits

Here’s a quick overview of the new AAK feature and benefits from WWDC 2025:

Feature	What’s new or improved?	What’s the impact or benefit?
Overlapping re-engagement windows	Multiple windows with conversion Tags	More granular re-engagement measurement
Configurable attribution windows	Custom per-network and per-type	Fine-tuned attribution behavior
Configurable attribution cooldown	Block overlapping attributions	Improved attribution accuracy
Country code in postbacks	Optional geo field with privacy	Better geo-targeting & reporting
Improved testability in settings	Dev postbacks tool in iOS Settings	Easier, faster testing

But there’s a catch, right?

All of this is genuinely good. Maybe even great, in some cases. 

But the problem with AAK is the same as SKAN 4. As you can see on our SKAN adoption board, adoption of SKAN 4, which was released all the way back in October 2022, is not even at 50% adoption yet.

Most of the big players are still on SKAN 3. Only TikTok is mostly on SKAN 4, while Meta, Google, and Snap are all basically SKAN 3. AAK was first released over a year ago in March of 2024, and there’s barely been a shift towards adoption. Apple Ads, which just started supporting Apple’s own attribution methodology, is also still on SKAN.

Instead of using Apple’s framework and tech, all the big players are doing different things in attribution and measurement, mostly around internal modeling based on more touchpoints, and sharing more information with MMPs for attribution purposes:

• Google just released Integrated Conversion Measurement
• Meta has AEM and Advanced AEM
• TikTok releases more data via Advanced SAN
• Snap has an Advanced SAN product

So the catch is this: it doesn’t matter how good AAK is if the ecosystem doesn’t support it. And it sure doesn’t look like a priority to most of the players right now.