What is it?
Setting a Customer User ID allows you to cross-reference users tracked by AppsFlyer with your own business user key identifier. The Customer User ID is specifically designed in accordance with your business logic - this is a free text field for you to enter whatever suits you. The data is available in the raw data reports, under the Customer User ID column.
How Does it Work?
The SDK provides a function allowing you to populate the Customer User ID in the dedicated field. Refer to the Set Customer User ID section of the SDK Integration Guides (iOS, Android, Unity) for more details.
Once the Customer User ID is set, each and every event tracked by AppsFlyer contains this ID. This allows you to cross-reference AppsFlyer data with your data, using the Customer User ID as key.
For example, one user with two devices can have the same Customer User ID. Each time they perform an event on either device, it is tracked under the same Customer User ID. Allowing you to clearly understand the true value of the user over both devices.
- It is highly recommended to set your Customer User ID as soon as possible, since it is only associated to events reported once the attribute has been set. Ideally it should be placed before the startTracking method API call to have the Customer User ID as part of the raw installation data.
- If you choose to work with integrated data partners such as Mixpanel or Swrve, you are required to set the Customer User ID for the integration to work effectively.