Skip to main content

Configure AppLovin Conversion API

Learn how to configure the AppLovin (Axon) Conversion API to send your Cometly conversions to AppLovin server-to-server.

How to Configure the AppLovin Conversion API

The AppLovin Conversion API (CAPI) lets Cometly send your conversion events directly to AppLovin's Axon platform server-to-server, so AppLovin can report and optimize on your conversions even when browser-based tracking is blocked or incomplete. It sends the events you already track in Cometly to AppLovin, matched to the AppLovin ad click that drove them and to the customer's hashed email, phone and customer id.
​

Setup takes a few minutes: pick a data-sharing mode, paste two keys from AppLovin Ads Manager, check the event map and click Save.
​

How it works

AppLovin adds a click id called aleid to your landing page URL every time someone clicks one of your AppLovin ads. The Comet Pixel records it as part of the visitor's journey. When Cometly later records a conversion for that visitor, it sends the event to AppLovin with that click id, along with the customer's hashed email, phone and customer id so AppLovin can match it.

  1. A visitor clicks your AppLovin ad and lands on a page with the Comet Pixel installed.

  2. The visitor converts, on your site or through a webhook, API or CRM event you send to Cometly.

  3. Cometly sends the mapped event to AppLovin's Conversion API server-to-server, using your space's Event Key.

For an event to be sent, the Cometly event must be mapped to an AppLovin event (see Step 4). Events you don't map are never sent.
​

Note: AppLovin is a Conversion API destination only. There is no AppLovin ad account to connect under Integrations, and you don't need to add anything to your ad URLs: AppLovin appends the aleid click id itself. Everything lives in the Conversion API tab of Events Manager.

Before you start

  • Admin access to AppLovin Ads Manager (ads.applovin.com). Only account Admins can open the Keys page where both keys live.

  • The Conversion API enabled on your AppLovin account. AppLovin enables it per advertiser; once it's on, a Conversion API Key appears on the Keys page. If you don't see one, ask your AppLovin representative to enable the Conversion API for your account.

  • The Comet Pixel installed on your landing pages, so Cometly can capture the aleid click id when an AppLovin visitor arrives.

  • Optional: the AppLovin Pixel on your site. When it runs alongside the Comet Pixel, Cometly also sends AppLovin's own browser id with each event, which improves match rates.
    ​


Step 1: Open the Conversion API settings

Go to Events Manager, open the Conversion API tab, and expand AppLovin.
​


Step 2: Choose a data-sharing mode

Under Manage Data Sharing, pick one:

  • Turn off data sharing: no events are sent to AppLovin.

  • Send all mapped events (Recommended): send every mapped event. Events without an AppLovin click are matched on hashed email, phone and customer id.

  • Send attributed events only: send only events whose journey includes an AppLovin click (aleid).
    ​

The mode saves as soon as you pick it, but nothing is sent until you store your keys in the next step.
​


Step 3: Paste your AppLovin keys

Once a mode other than Turn off data sharing is selected, the Configure AppLovin card appears with two fields:

  • AppLovin Event Key: the id of your AppLovin pixel. It's the same key that appears in your AppLovin Pixel code.

  • Conversion API key: the key that authorizes Cometly to send events to your account.
    ​

Both come from AppLovin Ads Manager: open your account menu and go to Keys (ads.applovin.com/account/api-keys). Copy the Event Key and the Conversion API Key and paste them into the matching fields.
​

⚠️ Important: The Conversion API key is encrypted before it is stored and is never shown again. When you come back to this page later, the key field is blank: leave it blank to keep the stored key, including when you change the Event Key. Paste a new key only when you want to replace the stored one.


Step 4: Check the event map

Cometly pre-fills the map with your standard events matched to AppLovin's standard web events. One map covers the whole space. Review it, add a row with Add mapping for anything missing (custom events included), and remove rows you don't want sent with the trash icon.
​

The default map:

Cometly event

AppLovin event

Purchase

Purchase

Lead

Generate Lead

Sign Up

Sign Up

Complete Registration

Sign Up

Initiate Checkout

Begin Checkout

Add To Cart

Add To Cart

Add Payment Info

Add Payment Info

Subscribe

Subscribe

View Content

View Item

AppLovin events you can choose from: Purchase, Generate Lead, Sign Up, Begin Checkout, Add To Cart, Add Payment Info, View Item, View Cart, Remove From Cart, Subscribe, Login, Search and Page View. These are AppLovin's standard web events; custom AppLovin event names aren't supported.
​


Step 5: Save

Click Save at the bottom of the AppLovin section. Cometly stores your Event Key, encrypts and stores the Conversion API key, and saves the event map. From this point on, every mapped conversion is sent to AppLovin.
​

Event mapping rules

  • One map and one Event Key per space. Every event goes to the same AppLovin pixel.

  • Multiple Cometly events can map to the same AppLovin event. For example, both Sign Up and Complete Registration map to Sign Up by default.

  • Only mapped events are sent. If a Cometly event isn't mapped, it is never sent to AppLovin.

  • Send purchases as Purchase. The order amount is sent in your space's currency, along with the transaction id, so AppLovin can report revenue.

Good to know

  • Once active, Cometly sends mapped conversions to AppLovin going forward. It does not backfill past events.

  • Events reach AppLovin about 15 minutes after Cometly records them.

  • AppLovin needs at least one identifier to match an event: a hashed email, a hashed phone, Cometly's customer id or the AppLovin Pixel's browser id. Events with none of these are not sent. Email and phone are hashed with SHA-256 before they leave Cometly.

  • Send attributed events only relies on the Comet Pixel having seen the aleid click id on the landing page. If the visitor landed on a page without the Comet Pixel, the click is unknown to Cometly and the event is not sent in that mode.

  • If you also run the AppLovin Pixel and it tracks the same event, don't map that event here too. AppLovin only removes duplicates that share a dedupe id, and the pixel's ids won't match Cometly's, so the conversion would be counted twice. Purchases that reach Cometly through a webhook, API or CRM, which the pixel never sees, are the usual reason to use this integration.
    ​


Troubleshooting

No conversions showing up in AppLovin

  • Confirm the mode isn't set to Turn off data sharing.

  • Confirm the Cometly event is mapped to an AppLovin event (Step 4). Unmapped events are never sent.

  • Confirm both keys are saved (Step 3). Until they are, every event is skipped with Event key or Conversion API key is missing.

  • Allow about 15 minutes for a new conversion to be sent.

  • In Send attributed events only mode, confirm the Comet Pixel runs on the landing pages your AppLovin ads point to.

Events show "Authentication failed, check the Conversion API key"

  • AppLovin rejected the stored key. It may have been revoked or regenerated in Ads Manager. Copy the current Conversion API Key from the Keys page, paste it into the key field and click Save.

Events show "Disallowed by mode"

  • The mode is Send attributed events only and the event's journey has no AppLovin click. Switch to Send all mapped events to send it matched on email, phone and customer id, or check that the Comet Pixel runs on the landing page.

Events show "Conversion action is not mapped"

  • Add the Cometly event to the map (Step 4) and click Save.

Events show "No click ID and/or user identifiers"

  • The event carried no email, phone or customer id, so AppLovin has nothing to match it on. Make sure your conversion events include the customer's email or phone.

Events show "HTTP 400"

  • AppLovin rejected the event, and the message carries its reason. Check that the Event Key is correct, then contact support with the message if it keeps happening.

I don't see a Conversion API Key on AppLovin's Keys page

  • The Conversion API hasn't been enabled for your AppLovin account yet. Ask your AppLovin representative to enable it; the key appears on the Keys page once they do.

I don't see AppLovin in the Conversion API tab

  • AppLovin is being rolled out to accounts in stages. Email support@cometly.com and we'll enable it for your space.
    ​

Need a hand with any of this? Email us at support@cometly.com.

Related Articles
Did this answer your question?