Firebase Analytics incorrectly logs engagement time while app is not active

Question

My app is using Firebase Analytics and linked with BigQuery. I found in BigQuery log that sometimes my app kept logging engagement time event when the app seems to be inactive. The behavior can be divided into 2 patterns:

Pattern 1: App keeps sending user_engagement event every one hour after app inactive.

Pattern 2: App was inactive for a long time (>1 hour). But when user come back, my app sent the first screen_view event with incorrect engagement_time_msec = ~amount of time since app last active.

Anyone has any idea what I could do wrong in my app. Since Firebase Analytics is not open source, I have no idea how this behavior could happen.

Answer 1

I finally found the root cause of incorrect engagement time. I found that Firebase Android SDK is not logging engagement time correctly when disable screen view tracking. I filed an issue here.

If you really need to disable auto screen tracking, you can use workaround I found below.

Warning This workaround may have side effect. Use it at your own risk.

I removed the following line from AndroidManifest.xml.

<meta-data android:name="google_analytics_automatic_screen_reporting_enabled" android:value="false" />

Then, use the following code in Activity's onResume for disabling automatic screen reporting instead.

override fun onResume() {
    FirebaseAnalytics.getInstance(this).setAnalyticsCollectionEnabled(false)
    super.onResume()
    FirebaseAnalytics.getInstance(this).setAnalyticsCollectionEnabled(true)
}