About Google Analytics for Firebase
If you're using Firebase to develop your apps, then Google Analytics is built in.
When you create a new Analytics account to report on one of those apps, you identify the app during the creation process, and data collected from that app is sent to the default property. You can also create a new mobile-app property within an existing account.
View the reports in either Analytics or the Firebase console.
Learn more about setting up Analytics to track your mobile apps.