Apple’s SKAdNetwork (SKAN) was introduced in 2018 to provide privacy-preserving attribution for iOS campaigns, replacing user-level tracking with aggregated, anonymized signals. Since the launch of App Tracking Transparency (ATT) in iOS 14.5, SKAN has become the primary attribution framework for most advertisers on iOS.
Now, with SKAN 4.0, Apple has significantly expanded the model—bringing new opportunities for marketers who can adapt their strategies to this evolving, privacy-first world.
What’s New in SKAN 4.0
- Multiple Postbacks for Better Insight
Previously, SKAN only sent one postback per install, containing limited information about early user behavior. SKAN 4.0 now offers up to three postbacks over time:
- Postback 1: 0–2 days after install
- Postback 2: 3–7 days after install
- Postback 3: 8–35 days after install
- Postback 1: 0–2 days after install
- This allows advertisers to capture more data about user engagement and monetization across the first month—crucial for apps with longer onboarding or monetization cycles.
- Coarse Conversion Values
In addition to detailed “fine” conversion values, SKAN 4.0 introduces “coarse” values (low, medium, high). This lets advertisers still get directional performance insights even when user privacy thresholds prevent sharing detailed data. - Crowd Anonymity Tiers
Apple’s “crowd anonymity” model determines how much data you receive based on the volume of installs per campaign. Higher install volumes unlock more detailed reporting. SKAN 4.0 now uses tiers that allow for partial data even in lower-volume scenarios. - Web-to-App Attribution
SKAN 4.0 now supports tracking conversions from Safari-based web ads to App Store installs—opening new retargeting and cross-channel possibilities. - Hierarchical Source Identifiers
Marketers can now use hierarchical campaign IDs (up to 4 digits) to encode more granular information about placements, audiences, or creative while still respecting privacy thresholds.
How to Adapt Your Media Buying Strategies
- Optimize for Early Engagement Signals
With multiple postbacks, you need to identify which in-app actions within days 0–2 correlate with long-term value. Optimizing campaigns for those early indicators will help you make faster, more informed bidding decisions. - Scale to Unlock More Data
Because crowd anonymity still limits granularity at low volumes, consolidating spend into fewer campaigns or creative groups can help push installs over the privacy threshold—unlocking fine conversion values and more actionable insights. - Use Coarse Values for Testing
Coarse values are less precise, but they still allow you to compare creative performance and audience segments when you can’t reach fine-value thresholds. Treat them as a “directional compass” rather than a precision instrument. - Leverage Web-to-App Flows
If your brand has strong mobile web traffic, integrating SKAN’s web-to-app capabilities can help recapture lost attribution from Safari and expand retargeting options. - Invest in Predictive Modeling
With longer feedback loops, machine learning models that predict LTV from early signals become more important. Partner with MMPs or UA platforms that specialize in SKAN-compliant modeling.
Final Thoughts
SKAN 4.0 is a step forward for iOS app marketing—it delivers more data while maintaining Apple’s privacy standards. For advertisers who adapt, the framework offers richer insights, better optimization windows, and new growth opportunities.