Google Firebase
Firebase App ID
- Open Firebase.
- Choose your project and open it.
- Click the "gear" and open Project Settings.
- Find your app and Copy the App ID.
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Firebase API Secret
- Open Google Analytics and choose the necessary account.
- Open Admin Settings at the bottom of the page.
- Find Datastreams > Choose your App and open App Stream details.
- Scroll down and in the Additional Settings click Measurement Protocol API secrets.
- There you will find Secret value.
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Custom events
If you can access your custom events in Firebase but not in Google Analytics/Google Ads, you need to mark them as key events.