> ## Documentation Index
> Fetch the complete documentation index at: https://help.airbridge.io/llms.txt
> Use this file to discover all available pages before exploring further.

# FAQ - Migrating to Airbridge

## Identifier Data Import

<AccordionGroup>
  <Accordion title="Does the imported identifier data affect the event count?">
    No, the device IDs and user IDs imported to Airbridge are only used to determine whether a user performed an event for the first time, or whether an event is a “first event.”

    Therefore, the event count available via Airbridge reports and raw data exports are not affected.
  </Accordion>

  <Accordion title="Do I have to import both device IDs and user IDs?">
    No, you do not have to import both device IDs and user IDs.

    Prioritize device IDs over user IDs because Airbridge determines first events using device IDs when sending postbacks to ad channels. This means that you should import device IDs to Airbridge to optimize your campaigns or assess your ad spend based on first events.

    User IDs should primarily be imported to improve the accuracy of the data available in Airbridge reports, not for postbacks.
  </Accordion>

  <Accordion title="For which specific events should I import the users’ identifiers to Airbridge?">
    You are advised to prioritize events that could have a direct impact on your ad spend if a first event. The most common events that may affect your ad spend include:

    * App install
    * Order complete
  </Accordion>
</AccordionGroup>

<link rel="alternate" hrefLang="en" href="https://help.airbridge.io/en/guides/migration-guide-faq" />

<link rel="alternate" hrefLang="ko" href="https://help.airbridge.io/ko/guides/migration-guide-faq" />