What happens if the advertiser app integrates multiple SDKs that all support SKAdNetwork?

The first call to registerAppForAdNetworkAttribution() generates the notification if the device has attribution data for that app, and starts a 24-hour timer. Subsequent calls to this method have no effect, and there is no need to worry about duplicates.

However, it's critical to ensure only one source is managing updateConversionValue(_:) calls. If you have more than one party making these updates, your data will quickly become messy because each party will likely define the meaning of a given conversion value differently.