Install Attribution

Install attribution connects an app install (or re-open) to the link that drove it. WarpLink uses a multi-tier match cascade to determine which link a user came from, with confidence scores that help you decide how to route the user.

Match Cascade

The server tries matching methods in order. The first successful match wins.

Priority	Method	Signal	Confidence	Platform
1	Referrer	Play Install Referrer	1.0	Android
2	Device ID	IDFV	1.0	iOS
3	Fingerprint	IP + UA + language + screen + timezone	0.40–0.85	Both
4	Raw signals	Device signals without pre-computed hash	varies	Both

The IP Gap Problem

The SDK cannot know its own public IP address, but WarpLink includes the request IP in fingerprint computation at click time. To solve this:

• The SDK sends raw device signals (not a pre-computed fingerprint) to the attribution endpoint
• The server computes the fingerprint hash using the request's IP address
• This ensures the SDK-originated fingerprint matches what WarpLink stored at click time

Confidence Scores

Score	Match Type	Recommended Action
1.0	Deterministic	Route directly to content
0.85	Probabilistic (< 1h)	Route to content
0.65	Probabilistic (< 24h)	Route to content
0.40	Probabilistic (< 72h)	Show suggestion or confirmation
< 0.3	Uncertain	Show generic onboarding

When multiple candidates match the same fingerprint, each additional match reduces confidence by 0.15 (e.g., two matches at < 1h = 0.70 instead of 0.85).

Click Deduplication

Click uniqueness is computed server-side at write time for perfect accuracy, never at the cache layer.

A click is considered unique per combination of link, IP address, and 24-hour window.

What attribution returns

When a match succeeds, the response identifies the link and how confident the match is:

• Matched link: the link the install is attributed to, with its resolved deep link and destination URLs and any custom parameters
• Match type: deterministic for an exact referrer or device ID match, or probabilistic for a fingerprint match
• Match confidence: a score from 0.0 to 1.0 you can use to decide how to route the user (see Confidence Scores above)

Deterministic matches come from the Play Install Referrer on Android or the IDFV on iOS. If a user who previously installed the app taps a link, the IDFV gives an exact re-engagement match. When nothing matches, the response says so, and you can fall back to generic onboarding.

Privacy

WarpLink's attribution is designed to be privacy-preserving:

• No IDFA (iOS) or GAID (Android): no advertising identifiers
• No cross-app tracking: IDFV is scoped to your vendor
• No ATT prompt: IDFV is exempt from App Tracking Transparency
• Hashed fingerprints: Probabilistic fingerprints are stored only as a one-way hash, never as raw signals
• HTTPS only: All signal transmission is encrypted