In-app event discrepancy between Firebase Analytics and Appsflyer

[Andrew]

Hi there,

We have used Appsflyer as our app analytics for quite some time and recently added Firebase.

What looks strange for us is that when we compare our main events data from adwords campaigns (that is: the event count for our most important events based on which google adwords campaign is it attributed to), it look quite different from the data in Appsflyer.

Is the attribution different between them? 

Firebase tends to show more in-app event count attributed to adwords, (like +100% more than Firebase).

(Discrepancy remains the same whether we choose cross-channel last click or Adwords preffered attribution in Firebase)