What the Install Referrer Is
The Google Play Install Referrer is the Play Store's way of telling an Android app where its new user came from. When someone taps a link to an app's Play Store listing, any referrer parameters on that link travel with them. After install, the app can ask the Play Store for that referrer through the Install Referrer API, along with timestamps for the click and the install.
For mobile attribution on Android, this is the most important signal there is. It is first-party data from the store, it does not depend on device IDs or user consent prompts, and it ties the install directly to the link that drove it.
What the API Returns
The Install Referrer library returns a small set of fields:
- Install referrer, the referrer string from the Play Store URL, usually URL-encoded parameters such as a click ID, campaign and source.
- Referrer click timestamp, when the user clicked through to the store listing, in client and server versions.
- Install begin timestamp, when the install started, also in client and server versions.
- Install version, the app version that was installed first.
- Google Play Instant, whether the user launched the instant experience in the past.
The current API replaced the older INSTALL_REFERRER broadcast, which Google deprecated and stopped sending in 2020. Apps read the referrer through the Play Install Referrer library, which calls the Play Store over a service connection.
How MMPs Use It
An attribution SDK reads the referrer on the app's first open and sends it to the MMP's servers. If the referrer contains a click ID that the MMP issued when the user tapped a tracking link, the install matches that click deterministically. No IP or user-agent matching is needed.
This is why deterministic attribution on Android is so much more reliable than on iOS. Every install that came through a Play Store link with a referrer can be matched exactly, regardless of whether the user allowed ad tracking.
Linkrunner matches installs deterministically first, using the Google Play Install Referrer, ad click IDs such as gclid and fbclid, device IDs where the user allows it, and Apple AdServices for Apple Ads. It falls back to IP and user-agent matching only when no deterministic signal exists. See mobile attribution for the full matching order.
Meta Install Referrer
Meta runs its own variant. For Meta app install ads on Android, the referrer contains campaign data that Meta encrypts, and the advertiser decrypts it with a key from the Meta app settings. That lets an MMP attribute Meta installs, including view-through installs from app promotion campaigns, from the referrer itself.
In Linkrunner, adding the Install Referrer Decryption Key in the Meta integration turns on this decryption, so Meta installs on Android are matched from the referrer rather than estimated.
Install Referrer and Fraud
The timestamps make the referrer a strong fraud check. In a real install, the attributed click happens before the user reaches the store listing, and installs begin seconds to minutes later. In click injection, a malicious app fires a click after the user is already in the store or the install has begun.
Comparing the attributed click time with the referrer click timestamp and install begin timestamp exposes those cases. Linkrunner's Fraud Control includes rule templates for click injection and install hijacking that use this kind of timing evidence, and can withhold postbacks from flagged installs so networks do not optimize toward them. Read more on fraud protection.
Limits to Know
- Play Store only. Installs from other Android stores or sideloaded APKs have no Play referrer.
- Links need parameters. A plain store link without referrer parameters gives the app nothing to match on.
- Read it early. The data is available for 90 days, but attribution is most accurate when the SDK reads and reports it on first open.