> ## Documentation Index
> Fetch the complete documentation index at: https://docs.linkrunner.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Remarketing & Reattribution

Remarketing lets you measure when existing users return to your app through your campaigns. Linkrunner tracks these returning users through **reattribution** — attributing a returning user back to the campaign that brought them back.

## How Reattribution Works

When a user who has already installed your app returns after a period of inactivity, Linkrunner checks whether that return can be attributed to a marketing campaign. This is called **reattribution**.

For a user to be reattributed, two conditions must be met:

1. **The user must have been inactive** for at least the configured **inactivity window** (default: 0 days).
2. **The reinstall must occur within the reattribution eligibility window** — the maximum time between an uninstall and reinstall for the return to count as a reattribution (default: 90 days).

If both conditions are satisfied, the user's return is attributed to the campaign associated with the ad interaction, and a **reengagement** record is created.

## Reattribution Triggers

A reactivation event is the event a user completes to come back to the app. Reactivation events trigger reattribution and signal a user's return.

Linkrunner supports two reactivation events:

* **App Install (Reinstall)** — The user reinstalls the app after previously uninstalling it. Linkrunner detects reinstalls using device identifiers (GAID on Android, IDFA on iOS).

* **Deep Link Open** — The user clicks a deep link and is redirected into the app. For reattribution to work, deep linking must be configured in your app and the `handleDeepLink` function from the Linkrunner SDK must be called when the app opens via a deep link. See the [deep linking setup guide](/features/deep-linking-setup) for configuration details.

**Prerequisites for reattribution tracking:**

* [Deep linking](/features/deep-linking-setup) must be set up in your app.
* The `handleDeepLink` function from the Linkrunner SDK must be implemented. Refer to your SDK guide ([React Native](/sdk/react-native#handle-deeplink), [Flutter](/sdk/flutter#handle-deeplink), [Android](/sdk/android#handle-deeplink), [iOS](/sdk/ios#handle-deeplink), [Unity](/sdk/unity#handle-deeplinks)) for details.
* Android backup configuration must be set up for reinstall detection on Android. Refer to your SDK guide ([React Native](/sdk/react-native#step-4%3A-android-backup-configuration), [Flutter](/sdk/flutter#backup-configuration), [Android](/sdk/android#step-3%3A-backup-configuration)) for details.

<Note>
  On iOS, ATT (App Tracking Transparency) permission must be granted by the user for reattribution to work. Without ATT consent, Linkrunner cannot access the IDFA needed to identify returning users.
</Note>

## Push Notification Campaigns

Remarketing campaigns also include push notification campaigns run through engagement platforms like **MoEngage** and **WebEngage**. These campaigns are tracked as remarketing campaigns within Linkrunner.

The flow is similar to a user opening the app via a Linkrunner link — the marketer creates a campaign on Linkrunner and uses the generated link in a push notification campaign on engagement platforms. When a user opens the app through the push notification link, Linkrunner attributes the return to that campaign.

## Understanding the Windows

### Inactivity Window

The minimum number of days a user must be inactive before they can qualify for reattribution. Linkrunner determines inactivity based on the **last app open** — the time since the user last opened the app is compared against the configured inactivity window.

|             |        |
| ----------- | ------ |
| **Default** | 0 days |

**Example:** With a 7-day inactivity window, a user whose last app open was 3 days ago would **not** qualify for reattribution. A user whose last app open was 10 days ago **would** qualify.

### Reattribution Window

The maximum time between an uninstall and reinstall for the reinstall to count as a reattribution.

|           |         |
| --------- | ------- |
| **Value** | 90 days |