Attribution Link — What It Is, Tracking Mechanism and Install Attribution

What Is an Attribution Link?

An Attribution Link is a URL containing special parameters for tracking traffic sources in mobile advertising. Each time a user clicks such a link in an ad, email, or post, the attribution platform records the click event and associates it with a unique identifier.

After the user installs the app and opens it, the attribution platform's SDK sends a request to the server with the device identifier. The server matches this identifier with the saved click and determines which source led to the install. This process is called post-install attribution and is the foundation for building ad channel performance reports — without it, every source appears equally effective.

An Attribution Link can be simple (only the source identifier) or contain dozens of parameters for granular breakdown: campaign type, creative, audience, geo, device, and even a specific influencer post. Modern attribution platforms support both deterministic matching by advertising ID and probabilistic matching using fingerprinting.

How Does an Attribution Link Work?

The attribution process through a link consists of four sequential steps: click, redirect to the store, install, and verification. Each step is handled by the attribution platform, which links them into a single chain of events.

Click-Install Mechanism

When a user clicks an Attribution Link, the browser or webview sends a GET request to the attribution platform's server. The server creates a record with the click identifier, IP address, user-agent, referrer, and all passed parameters. The server then redirects the user to the App Store or Google Play to the app page.

After installation and first launch, the app (via SDK) sends a request to the platform with the device advertising ID (IDFA on iOS, GAID on Android). The platform searches for a click record containing the same IP, user-agent, and timestamp within the attribution window, and links the install to that click. The attribution window defaults to 7 days for clicks and 1 day for view-through impressions, but can be configured per campaign.

Fingerprinting and Probabilistic Attribution

If the device advertising ID is unavailable (the user has limited tracking in settings), the platform uses fingerprinting — a probabilistic matching method based on a set of indirect signals. The signature includes IP address, OS type and version, device model, language, time zone, screen resolution, and an exact timestamp. A combination of 6–8 such parameters yields a match probability of 95–97% on Android and 90–94% on iOS within a 5-minute window.

Attribution platforms continuously improve fingerprinting algorithms, adding machine learning to filter false matches. For example, AppsFlyer Privacy Cloud uses aggregated data and differential privacy for accurate attribution without collecting personal data — this is especially relevant after the introduction of App Tracking Transparency (ATT) on iOS and GAID restrictions on Android.

Attribution Link Structure and Parameters

An Attribution Link has a standard URL structure with required and optional parameters. Required parameters define the source and campaign, while optional ones detail the breakdown and link behavior.

curl -X POST "https://api.appsflyer.com/onelink/v1/build" \
    -H "Authorization: Bearer YOUR_API_TOKEN" \
    -H "Content-Type: application/json" \
    -d '{
    "brand_domain": "app.onelink.me",
    "app_id": "id123456789",
    "campaign": "spring_sale_2026",
    "media_source": "facebook_ads",
    "deep_link": "myapp://sale/spring"
}'

The campaign parameter specifies the ad campaign name, adgroup — the ad group, and creative — the specific creative. The deep_link parameter sets the deep link for already installed users. The click_label parameter allows distinguishing different buttons or positions within a single creative. This level of detail enables the marketer to see not only which channel works but also which button text or image brings more conversions.

Custom parameters af_sub1 – af_sub5 allow passing any additional information specific to a particular campaign: partner ID, audience type, A/B test variant. Based on these parameters, the attribution platform builds segmented reports, giving the marketer the ability to optimize the budget at the micro-segment level.

Mobile Attribution Platforms

The mobile attribution market features several major platforms, each offering its own Attribution Link format, SDK set, and algorithms. The choice of platform depends on the tool stack, audience geography, and data privacy requirements.

AppsFlyer

The largest attribution platform with support for OneLink, which combines deep linking and attribution in a single link. The AppsFlyer SDK supports all major platforms (iOS, Android, Flutter, React Native, Unity) and provides Privacy Cloud for attribution without collecting personal data. A distinctive feature is support for web campaign attribution in addition to mobile.

Adjust

The Adjust platform (acquired by AppLovin) offers its own link format with a focus on data protection. Adjust was the first platform to implement private fingerprinting without storing IP addresses. The Adjust SDK supports Kotlin Multiplatform and SwiftUI, and the dashboard provides real-time reports with less than 30 seconds delay from click to display.

Branch

Branch specializes in universal links (Universal Ads) and offers deeper deep linking integration than traditional attribution platforms. Branch Links work across all platforms including desktop and Smart TV, and the attribution system uses a device graph to link a user to a source even without IDFA. Branch also offers a free tier for startups up to 10 thousand installs per month.

Platform Comparison

When choosing a platform, it is important to consider not only the functionality of the Attribution Link but also compatibility with ad networks. For example, Facebook requires MMP (Mobile Measurement Partner) certification, which all three platforms have, but the depth of integration varies: AppsFlyer provides the most detailed breakdown by Facebook creatives, Adjust for TikTok and Snapchat.

Setting Up an Attribution Link in a Project

Setting up an Attribution Link involves two stages: integrating the attribution platform's SDK into the app and creating the links themselves for ad campaigns. Let us walk through the process using AppsFlyer as an example — the most popular platform.

Generating a Link in the Dashboard

In the AppsFlyer interface, select the app, link type (OneLink), set the source and campaign. The system automatically generates a URL like https://app.onelink.me/{id}?... with the chosen parameters. The ready link can be copied and pasted into an ad on the advertising platform. For mass generation, the API is used — for example, when creating 10 thousand unique links for influencers.

https://app.adjust.com/abc123?campaign=spring_sale&adgroup=banners&creative=banner_v2&deep_link=myapp://sale&click_label=header_cta

The above request creates a OneLink link via the AppsFlyer REST API. The brand_domain parameter sets the subdomain, app_id — the iOS/Android app identifier. The API returns a ready link that can be immediately used in a campaign. This approach automates link creation for thousands of campaigns without manual copying in the dashboard.

SDK Integration for Verification

For correct attribution, the platform SDK must be initialized when the app starts and send install events to the server. On iOS, integration is done via AppDelegate, on Android — via Application or the main Activity. The SDK automatically collects the device identifier and sends it along with first launch data.

After SDK setup, all clicks on Attribution Links will automatically be matched with installs in the attribution dashboard. The marketer sees a report with breakdown by sources, campaigns, creatives, and geo. Additionally, event-based conversions can be configured — for example, registration, purchase, or level completion — and each is tied to the original Attribution Link. This provides full end-to-end analytics from click to user LTV. Without such linking, the marketer cannot determine which users generated the most revenue and must rely on average channel metrics, leading to inefficient ad budget allocation.