AdAttributionKit

Definition

AdAttributionKit is Apple's ad attribution framework, introduced in iOS 17.4, that reports privacy-preserving install and re-engagement postbacks for advertised apps installed from the App Store or an alternative app marketplace.

It is SKAdNetwork's successor and keeps SKAN's entire privacy model — crowd anonymity, hierarchical source identifiers, three delayed postbacks, the same 6-bit conversion value. What it adds is the part SKAN never had: re-engagement measurement, support for marketplaces other than the App Store, and configurable windows. The two frameworks run side by side today, and a correctly instrumented ad can produce postbacks from both.

What it changes relative to SKAdNetwork

The privacy architecture is unchanged, so nothing you learned about crowd anonymity or conversion value encoding is wasted. The differences are in scope and control.

Re-engagement is the substantive addition. SKAN could only ever answer "which ad caused this install"; AdAttributionKit can also answer "which ad brought this existing user back", which is the question every retargeting budget has been spending against blind since 2021.

The three roles and the calls each one makes

Instrumentation splits across a publisher app that renders the ad, the advertised app that gets installed or reopened, and an ad network that signs the impression and receives the postback.

import AdAttributionKit

// The ad network hands you a signed JWS describing the advertised item.
// AdAttributionKit verifies the signature; a bad one throws here rather
// than silently producing an unattributable impression.
let impression = try await AppImpression(compactJWS: signedPayload)

// View-through: the ad was on screen but not tapped.
try await impression.beginView()
// ... ad is visible ...
try await impression.endView()

// Click-through: opens the store or the marketplace product page.
try await impression.handleTap()

import AdAttributionKit

// Fine value is the 6-bit payload (0–63). Coarse is what survives when
// the install cohort is too small to carry the fine value.
try await Postback.updateConversionValue(
    fineConversionValue: 12,
    coarseConversionValue: .medium,
    lockPostback: false
)

// lockPostback: true closes the current window early. It does NOT send
// the postback immediately — the randomised delay still applies.

Getting a copy of your own postbacks

Postbacks go to the ad network, not to you. To receive a copy of the ones your app wins, declare an endpoint in Info.plist. AdAttributionKit uses a different key from SKAN's, and an app instrumented for both wants both keys present.

<!-- AdAttributionKit copies -->
<key>AttributionCopyEndpoint</key>
<string>https://postbacks.example.com</string>

<!-- SKAdNetwork copies, for as long as you also run SKAN -->
<key>NSAdvertisingAttributionReportEndpoint</key>
<string>https://postbacks.example.com</string>

<!-- Development builds only. Never ship this true. -->
<key>AdAttributionKitDeveloperMode</key>
<true/>

• The endpoint must be HTTPS and must accept a POST with a JSON body.
• Apple appends its own well-known path to the host you declare, so register the origin and let the framework choose the path.
• Respond 200 quickly. A timeout or a 5xx is a lost postback, and there is no way to ask for it again.
• Developer mode shortens the delays to seconds so you can test end to end, and marks the resulting postbacks as test traffic — which is also why shipping it enabled would poison your production reporting.

What to do about it now

Apple has not announced a SKAdNetwork end-of-life date, and SKAN remains fully supported, so this is not a migration with a deadline attached. It is also not a reason to defer: the frameworks coexist, and AdAttributionKit is the only path to re-engagement measurement and to attribution for installs from alternative marketplaces under the EU's Digital Markets Act.

The framework's surface has moved more than once — iOS 18.4 added configurable and overlapping conversion windows, coarse region data in postbacks, and better developer-mode testing. Check Apple's AdAttributionKit documentation and the WWDC sessions against your target OS version before committing to a schema.