Ad Attribution (AdAttributionKit)

You can't optimize paid traffic you can't measure. AdAttributionKit is Apple's privacy-preserving attribution framework — interoperable with SKAdNetwork, and the go-forward path (it also works in alternative marketplaces). This skill covers the advertised-app side: what an indie running paid campaigns must implement and how to design conversion signals that survive privacy thresholds.

Note the seam: Apple Ads attribution uses the AdServices framework, not AdAttributionKit — campaigns there are measured in the Apple Ads console (see app-store/apple-search-ads). This skill is for every other paid channel (ad networks, social, publishers).

When This Skill Activates

• Running or planning paid user acquisition outside Apple Ads
• "How do I know which campaign drove installs?" / measuring re-engagement ads
• Designing or debugging conversion values / postbacks
• Migrating from SKAdNetwork (fully interoperable — registered networks need no re-enrollment)

How it works (the 60-second model)

Ad network signs an ad (compact JWS impression) → publisher app shows it → user installs (or re-engages) → after a privacy-delayed measurement window, a postback with your conversion info goes to the ad network (and optionally to you). Attribution requires no user tracking; the price is coarser data, governed by crowd anonymity.

Conversion-value strategy (the part that's actually yours)

• Two granularities: fine value 0–63 and coarse low/medium/high. Low crowd sizes downgrade fine → coarse and can trim the 4-digit campaign source-identifier to as few as its first 2 digits — so encode what matters most (campaign family, geo tier) in the first two digits, detail in the rest.
• Map values to revenue-predictive early behavior (completed onboarding, trial start, first purchase), not vanity events. 64 slots go fast; reserve ranges (e.g. 0–15 activation, 16–47 monetization ladder, 48–63 reserved).
• Update with updateConversionValue(_:) / PostbackUpdate; set lockPostback when the value is final to schedule transmission (still privacy-delayed, never instant).
• Re-engagement postbacks are separate from install postbacks: update them independently via conversionTypes (.install / .reengagement); the first re-engagement update must land within 48 hours.
• Multiple simultaneous re-engagement campaigns need conversion tags (iOS 18.4+): read the tag from the re-engagement URL's query items, store it, and pass it in PostbackUpdate — without a tag, updates hit only the most recent conversion.

Publisher-side mechanics (if your app also shows ads)

• Click-through: UIEventAttributionView over the tappable ad + appImpression.handleTap() within 15 minutes of creating the impression.
• View-through: beginView()/endView() on the same instance; ≥2 seconds on screen to count; one open view-through per network per advertised app.
• SKOverlay / SKStoreProductViewController: attach the impression — they count view on present, click on tap.

Attribution windows & cooldowns (iOS 18.4+ configurability)

• Defaults: 30 days click-through, 1 day view-through (install ads).
• Override per ad network and interaction type in Info.plist (AdAttributionKitConfigurations → AttributionWindows); you can ignore "view" or "click" (not both) per network.
• Set cooldowns (install-cooldown-hours, reengagement-cooldown-hours) so a re-engagement tap minutes after an install isn't double-attributed.
• Country-level postback data (iOS 18.4): storefront country at install, gated behind an extra crowd-anonymity tier — a bonus signal when volume allows, never guaranteed.
• Overlapping re-engagement conversions require opting in: EligibleForAdAttributionKitOverlappingConversions = YES in Info.plist.

Testing — never ship blind

• Developer Mode → Settings → Developer → Ad Attribution Testing: removes time randomization, shortens all conversion windows, sends postbacks on demand — full end-to-end rehearsal in minutes instead of days.
• Point development postbacks at a separate dev endpoint, never production: they're signed with a different key (kid), the network ID is always development.adattributionkit, and the advertised item ID may be 0 from Xcode.
• ✅ Verify the postback pipeline before spending a dollar. ❌ Debugging attribution after a live campaign burns budget on unmeasurable installs.

Checklist

• Conversion-value map documented (0–63 + coarse fallback + first-2-digit priority)
• lockPostback fired once value is final; re-engagement first update < 48h
• Conversion tags wired if >1 re-engagement campaign runs at once
• Cooldowns configured; windows tuned per network where defaults don't fit
• Dev-endpoint postback rehearsal done in Developer Mode
• Campaign readout joined with growth/analytics-interpretation (source-type funnel) — attribution tells you which ad, App Analytics tells you what they did after

References

• https://developer.apple.com/documentation/adattributionkit
• https://developer.apple.com/videos/play/wwdc2024/10060/ (Meet AdAttributionKit)
• https://developer.apple.com/videos/play/wwdc2025/221/ (What's new in AdAttributionKit)
• Related skills: app-store/apple-search-ads (Apple Ads uses AdServices, not this), growth/analytics-interpretation, growth/store-growth-audit (P7.3 halo tracking)