Apple's introduction of App Tracking Transparency limits the use of traditional user-level mobile measurement. Starting with iOS 14.5, the iOS Advertising Identifier (IDFA) is available only for end-users who consent to share their data (opt-in).

The alternative offered by Apple is SKAdNetwork, a privacy-centric framework for aggregate campaign measurement, which was originally introduced with iOS 11.3 but has been updated significantly for iOS 14. Ad network partners who are registered with SKAdNetwork can receive automatic "SKAdNetwork postbacks" when there is an app install, whether the end-user opted in to sharing their data or not.

Singular's SKAdNetwork solution, SKAN, gathers the data that advertisers need using an information exchange between the end-user's device, the ad network, and Singular (as the MMP).

• The SKAdNetwork postback is sent from the device to the ad network + to the MMP.
• The conversion value and its meaning are sent from the MMP to the ad network.
• The campaign ID and its meaning are sent from the ad network to the MMP.

Data flow diagram for Singular's Secure SKAN

1. Registering With SKAdNetwork

Ad network partners must register with Apple as a prerequisite to using SKAdNetwork. Apple will assign the partner an "ad network ID".

2. Handling the SKAdNetwork Postback

Option A (Recommended): Secure SKAN

Use a 307 redirect to allow Singular to receive the same SKAdNetwork postback sent from the device.

When you receive a SKAdNetwork postback for an advertiser who uses Singular as their MMP, use a 307 redirect to allow Singular to receive the same postback. Redirect the postback to Singular's dedicated skan_postback endpoint.

The redirect should also include some additional parameters in the URL (refer to the Ad Network fields). Here is an example for a full URL you could redirect the postback to:

"https://skadnetwork.singular.net/api/v1/skan_postback?adn_campaign_id=102&adn_campaign_name=My%20Campaign"

See the parameter reference for more details.

Option B: Sending the contents of the SKAdNetwork postback to Singular

As an ad network partner, you can use the skan_postback endpoint to send Singular a postback containing the entire payload of the postback from SKAdNetwork, unmodified. The postback should also contain some additional parameters.

The postback sent to Singular may look as follows:

{
 "version": "3.0",
 "ad-network-id": "com.example",
 "campaign-id": 42,
 "transaction-id": "6aafb7a5-0170-41b5-bbe4-fe71dedf1e28",
 "app-id": 525463029,
 "attribution-signature": "MDYCGQCsQ4y8d4BlYU9b8Qb9BPWPi+ixk\/OiRysCGQDZZ8fpJnuqs9my8iSQVbJO\/oU1AXUROYU=",
 "redownload": true,
 "source-app-id": 1234567891,
 "fidelity-type": 1,
 "conversion-value": 20,
 "did-win": true,
 "skan_ip": "136.25.2.194",
 "skan_timestamp": 1601555400,
 "adn_campaign_id": "102",
 "adn_campaign_name": "My Campaign"
}

See the parameter reference for more details.

3. Decode the SKAdNetwork Conversion Value

After you send Singular an SKAdNetwork postback using one of the methods above, you may want to decode the meaning of the conversion value.  Singular can support this in two ways.

Option A: Conversion Event Postback (coming soon)

Singular can send you back a notification postback containing information about the SKAdNetwork conversion event.

The goal is for you to save and process the conversion information, just like you do with postbacks that Singular sends about identifier-based or probabilistic attributions and events.

Singular will work with your team to learn which endpoint you want the postbacks sent to and to configure a postback template that is convenient for you to process.

As an example, a postback that Singular sends to a partner could look like this (with Singular postback macro syntax):

{
 "transaction-id": {SKAN_POSTBACK.TRANSACTION_ID},
 "conversion_event":{CONVERSION.PARTNER_CONVERSION_NAME},
 "is_attributed":{SKADNETWORK_IS_VALID},
 "original-conversion-value":{SKAN_POSTBACK.CONVERSION_VALUE},
 "mmp-conversion-name":{CONVERSION.ADVERTISER_CONVERSION_NAME},
 "mmp-conversion-value":{CONVERSION.ADVERTISER_CONVERSION_VALUE},
 "mmp-conversion-currency":{CONVERSION.ADVERTISER_CONVERSION_CURRENCY},
 "advertiser-app":{SKAN_POSTBACK.APP_ID},
 "attribution-type":"skadnetwork",
 "mmp":"singular"
}

See the reference section for all macros available with SKAdNetwork conversion event postbacks.

Option B: Use the SKAN Conversion Info API

Singular also hosts a pull API that allows integrated partners to retrieve the conversion model mapping.  This 

This API simply returns the configured conversion model for a given app(s), provided the following requirements have been met:

• The advertiser app has an active configured Conversion Model.
• The advertiser has an active Partner Configuration created for the partner.
• Partner has access to the Partner Portal to retrieve an API Key.

See our supporting technical documentation for this API for more information on request/response specifications and examples.

4. Handling the Campaign ID

If you use the Secure SKAN method to report SKAdNetwork postbacks to Singular, you can pass the information to Singular via your analytics integration with Singular.

Prerequisites:

• Ensure your ad network is already integrated with Singular attribution.
• Register for SKAdNetwork and have an "ad network ID" issued by Apple.

1. Gather requirements: Review What is a Singular SKAdNetwork Integration? to understand the integration details and options available.
2. Fill out the integration form for Singular's SKAdNetwork solution.
3. Receive our integration team's reply: The Singular integration team will review your form and let you know if we have any questions or if we have all the information we need.

4. Test the Integration: After Singular finishes creating the integration, we will contact you to let you know how you can test the integration on your end.

This section documents the API endpoint and parameters that Singular supports for inbound SKAdNetwork postbacks to Singular (device → Singular, Ad Network → Singular).

Endpoint: https://skadnetwork.singular.net/api/v1/skan_postback
Method: POST
Parameters:
*indicates a required value

Request Specifications (Singular → Ad Network)

This section documents available values that Singular can include in SKAdNetwork conversion event postbacks from Singular to partners. These values are intended to provide conversion value information to the ad network.

The values are available in both GET and POST payloads.

Use conversion_info to retrieve Singular’s record of conversion model information about a specific advertiser's SKAdNetwork conversion value.