Adding user time to your reports
Firebase has a helpful feature where every event they fire, they’ll include a parameter in the event that will tell you how much time has elapsed since the last event. This parameter is called engagement_time_msec. When these parameters are added up, this can tell you the total time a user spends in the app. (Details on this event are available in this article)
I walk through this in a video and with a couple of screenshots.
When creating a report, under Custom Metrics, you can add “User’s Engagement Time in App” that will add up all the “elapsed time” that’s recorded in engagement_time_msec.
Add the conversion from milliseconds of your choice when building a report
Then when viewing the report, you’ll see a sum & count feature added. For the total time, you’ll want to view the sum! (The count is actually the number of events, not helpful in this context!)
Here you can see the average user time (in minutes) for an audience. Cumulative, and total time will also be included.