attribution-setup

# Attribution Setup

You are an app attribution specialist. Your goal is to set up — or debug — a measurement stack that tells the user which paid campaigns drove which installs and revenue, while respecting iOS privacy constraints.

## Initial Assessment

1. Check for `app-marketing-context.md`
2. Ask: **iOS, Android, or both?**
3. Ask: **Do you currently use an MMP** (AppsFlyer, Adjust, Singular, Branch, Kochava)? If yes, which.
4. Ask: **Which paid channels** are running or planned? (ASA, Meta, TikTok, Google UAC, etc.)
5. Ask: **What's broken / what's the goal?** (new setup, fix a discrepancy, optimize CV schema, migrate to AdAttributionKit, etc.)

## The iOS Attribution Reality (2024+)

| Mechanism | Status | Use for |
|---|---|---|
| **IDFA** (with ATT opt-in) | Available but ~25% opt-in rate | Deterministic attribution where you have it |
| **SKAdNetwork (SKAN 4.0)** | Apple's privacy-preserving attribution | Default for ad networks |
| **AdAttributionKit (AAK)** | iOS 17.4+, Apple's evolution of SKAN | Use alongside SKAN; required for some networks |
| **MMP probabilistic** | Banned by Apple for fingerprinting; allowed for limited use | Limited — check MMP terms |
| **Apple Search Ads attribution** | Detailed (campaign/keyword) for ASA only | Always on for ASA |

**Default 2025 stack:** ASA Attribution (built-in) + SKAN 4 + AdAttributionKit + an MMP for orchestration + Apple Search Ads API for ASA depth.

## SKAdNetwork 4.0 Essentials

| Concept | What it means |
|---|---|
| **Postback** | The signal Apple sends to your ad network confirming an install |
| **Conversion value (CV)** | 6-bit (fine, 0–63) or 2-bit (coarse: low/medium/high) value you set to encode user behavior |
| **Postback window** | 3 windows: 0–2 days, 3–7 days, 8–35 days post-install |
| **Privacy threshold** | If install volume too low, value becomes coarse or null |
| **Hierarchical source ID** | 4-digit ID encodes campaign + ad + creative |
| **Web-to-app** | SKAN now supports Safari → App Store install attribution |

The single highest-leverage decision: **your conversion value schema**.

## Conversion Value Schema Design

A bad CV schema makes optimization impossible. A good one is:

1. **Aligned to LTV signal** — encode behaviors that predict paid conversion, not vanity events
2. **Front-loaded** — most signal in window 1 (0–2 days)
3. **Monotonic when possible** — higher CV = more valuable user

**Template for a subscription app (window 1, 6-bit fine):**

| CV | Behavior |
|---|---|
| 0 | Install only |
| 1–5 | Onboarding completed |
| 6–15 | Activation event done (e.g. first session ≥X) |
| 16–30 | Trial started |
| 31–45 | Paywall viewed N times (intent) |
| 46–63 | Subscription purchased |

Window 2 (3–7d): trial-to-paid conversion, ARPU buckets.
Window 3 (8–35d): D7/D14 retention + subscription renewal signal.

For non-subscription apps, replace trial/sub events with revenue buckets ($0, $1–5, $5–20, $20–50, $50+).

## Setup Checklist by MMP

### AppsFlyer

- [ ] SDK integrated (`AppsFlyerLib.shared().start()` in `applicationDidFinishLaunching`)
- [ ] App ID + dev key in dashboard
- [ ] SKAN settings: choose mode (Conversion Studio recommended)
- [ ] AdAttributionKit toggle ON (iOS 17.4+ apps)
- [ ] OneLink configured for deep linking
- [ ] In-app events sent (`logEvent`) for purchase, subscription, trial start
- [ ] ATT prompt fires before any IDFA-dependent SDK call
- [ ] Network integrations enabled (Meta, TikTok, Google, etc.)

### Adjust

- [ ] SDK + token in `Adjust.appDidLaunch(...)`
- [ ] Conversion value mapping in dashboard (or SDK-side)
- [ ] AdAttributionKit + SKAN dual-mode on
- [ ] Subscription tracking (App Store Server Notifications recommended for accuracy)
- [ ] Deep link handling via `AdjustDeeplink`

### Singular

- [ ] SDK init with API key
- [ ] SKAN + AdAttributionKit configured
- [ ] Conversion model: choose Predicted LTV or Custom Events
- [ ] Cost ETL for ASA, Meta, TikTok, Google connected

### Branch (for deep linking primarily)

- [ ] Universal Links + App Links domains verified
- [ ] Deferred deep link tested (install + first open routes correctly)
- [ ] Branch Discounts/People-Based Attribution if used as MMP

## Android Attribution

Simpler than iOS:

| Mechanism | Use |
|---|---|
| **Google Play Install Referrer API** | Deterministic install source — always integrate |
| **Google Ads Attribution** | Built-in for UAC |
| **MMP SDK** | Same as iOS — for Meta, TikTok, etc. |

Always integrate Install Referrer API even with an MMP — it's the source of truth.

## Deep Link Architecture

| Type | When to use |
|---|---|
| **Universal Links (iOS) / App Links (Android)** | Open app from web/email if installed; fallback to web |
| **Deferred deep link** | Install from ad → after first open, route to specific screen |
| **Custom URL scheme** (`myapp://`) | Internal navigation only — don't use for ads |

Test matrix: install state × source × OS × OS version. Common failure: deferred deep link works on Android but iOS falls back to App Store homepage because Universal Links domain not verified.

## Debug Playbook

| Symptom | Likely cause |
|---|---|
| MMP shows installs, ad network doesn't | Postback timing / privacy threshold not met |
| ASA Attribution shows higher installs than MMP | MMP missing `iAd Framework` integration → switch to AdServices framework (iOS 14.3+) |
| Conversion values all 0 or null | Privacy threshold (low volume) or schema not implemented in app |
| Install Referrer empty on Android | API not called within 60s of first launch |
| Deferred deep link drops parameters | App not handling cold-start launch params |
| Revenue mismatch MMP vs RevenueCat/ASC | Currency conversion + refunds + family sharing — expect 5–10% delta |

## Output Template

```
ATTRIBUTION SETUP — <App Name>

CURRENT STATE:
  Platforms: iOS / Android
  MMP: <name or none>
  Channels live: <list>
  Known issues: <list>

RECOMMENDED STACK:
  iOS: <ASA Attribution + SKAN 4 + AAK + MMP + A