I've run a Google Ads campaign. How can I know the ID of the users who dowloaded the app coming from that campaign?

Hi @mariocamus ,

Thanks for the answer Saish! I am wondering if you are possibly looking into Attribution? This will help you send events of when the user installed the device. Amplitude integrates with many third-party attribution partners from which you can send attribution data to Amplitude via the Attribution API. Here is a list of our partners: https://amplitude.com/partners.
 
To cover our bases, I'd like to go over how the AppsFlyer<>Amplitude integration works:
 
AppsFlyer uses the Amplitude Attribution API to send data to Amplitude. We store all attribution events but do not display all of these events in the Amplitude UI. Attribution events will only show up in Amplitude once Amplitude matches the AppsFlyer event to an existing Amplitude user. If we receive non-attribution events with user information that matches the attribution events, the attribution events will then be ingested into Amplitude and subsequently be displayed in the UI. Otherwise, the attribution event will be dropped. This allows attribution information to be sent without worrying about polluting Amplitude with events from people who never actually use the app.
 
There are a few key points to keep in mind:

• Attribution is matched to Amplitude users/events via the Advertising ID (IDFA/IDFV or ADID). Therefore, you must send the Advertising ID for attribution requests and you must set the idfa, idfv, and adid fields for users in Amplitude as the Advertising ID. If you are using the iOS SDK or Android SDK, you can enable tracking of the Advertising ID by following the instructions linked here IOS SDK  and here Android SDK. If you are using JS SDK or React Native, these do not have the functionality to collect Advertising ID automatically due to Google's and Apple's privacy rules around advertising ID and web tracking. You will have to send the Advertising ID through our HTTP API endpoint so that Amplitude can match attribution data/events. See keys in our HTTP API V2 doc.
• If attribution events cannot be matched to an existing user then it is held for up to 72 hours for potential user matching. If an event is not logged for a matching user within 72 hours of receiving the attribution data, then the attribution data will be dropped. 

 
To summarize, in order for a AppsFlyer event to show up in Amplitude, there must be a non-attribution event that has a matching Advertising ID already in Amplitude or sent to Amplitude within 72 hours of receiving the AppsFlyer event. Lack of Advertising ID and lack of matching events are the two most common reasons that attribution events do not make it into Amplitude.
 
Unless I have misunderstood the question? I hope this helps but let me know if I have misunderstood and require further help!
 
Kind Regards,
Denis