What is Axon?

Axon is AppLovin’s AI-powered advertising engine that powers its performance marketing solutions. It uses large-scale machine learning models to match advertiser demand with publisher supply in real time. By analyzing extensive in-app behavioral, device, and engagement data, Axon predicts which users are most likely to install, engage with, or make purchases within an app. The system continuously trains and optimizes to improve return on ad spend (ROAS) and campaign efficiency across AppLovin’s advertising ecosystem.

Product Type: Advertising

Integration Type: Starter Kit & ID Sync

Capabilities

• Captures aleid and alart from URL parameters and stores them in first-party storage.
• Refreshes stored Axon identifiers and resets their expiration when new values are detected.
• Adds Axon identifiers to server-side events for attribution and campaign measurement.
• Supports downstream audience workflows by persisting Axon identifiers across events.

Sync Details

• IDs:
  • aleid – An AppLovin click identifier appended to website URLs after a user clicks an AppLovin ad, used to identify and attribute AppLovin-driven traffic and conversions.
  • alart – An Axon identifier passed as a URL parameter (commonly for app users) that is used for campaign measurement and event enrichment.
• Description:
  • The sync captures aleid and alart from URL parameters.
  • Each value is stored in first-party storage for a configured duration.
  • Values are refreshed when new data is detected, or when the Cookie Lifetime elapses (whichever occurs first).
  • The identifiers are added to server-side event payloads for attribution or targeting.
• Server-side Event Payload: Server-side Event Payload: Upon completion of all vendor's sync, the server-side events will incorporate all resolved identifiers as described above. The following object will be appended to the context.providers property within the event's JSON payload.

{
   "axon": {
     "aleid": String
     "alart": String
   }
}

• Cookie Name:
  • Cookie: _meta_axon_aleid, _meta_axon_alart
  • IndexedDB: [your storage prefix]_axon_aleid, [your storage prefix]_axon_alart
  • For a general guide on ID Sync validation, see here.

Sync Setup Guide

Add a Axon Sync in MetaRouter

To gather the aleid, alart, you must add anAxon sync.

1. From the Pipelines page, find the pipeline associated with the web property you’d like to add a sync to. Hover over the three dot dropdown and select “Build AJS File.”
2. In the Identity Syncs section, select the Axon sync.
3. Fill out the following fields:
   1. (Optional) Cookie Lifetime (in days) – How long a synced identifier remains in first-party storage. When expired or no longer detected, the sync will re-trigger. Example: 365
4. Scroll down and click the Save and Build File button.
5. Deploy your AJS file to propagate changes to your web property.