To Firebase Analytics, or Not To Firebase Analytics?


June 3, 2016

Introducing Guest Contributor: Heidi Yee

Heidi Yee

Heidi Yee

Heidi recently interned with Analytics Pros after finishing up the iOS Accelerator Program at Code Fellows. Previously, she attended University of Washington for Industrial Engineering and worked at Boeing for three years.

Firebase Analytics was released during her stay with us – so she was one of the first people to dig into the platform and its integration with Google Tag Manager and Google Analytics. This post reflects her takeaways regarding those platforms.


So you have a mobile app and you want to know if you should switch from Google Analytics to Firebase Analytics—that’s a great question! To help you find the answer, we’ve outlined the key differences between the two to help you decide how to best measure your mobile app analytics.

Firebase Analytics vs Google Analytics

Firebase Analytics: The Pros

  • Firebase Analytics comes with a new analytics UI that is designed for mobile and will populate automatically as soon as you install Firebase’s SDK into your app—at no additional cost. All you have to do is create a Firebase instance in your project and the Firebase SDK does the rest. (Find the automatic event calls here.
  • Additionally, Firebase comes with a very easy UI to create campaigns for ad network and deep link attribution. This is a big improvement from Google Analytics and allows for easier attribution data to be more easily obtained than with Google Analytics.
  • Firebase comes with the use of Firebase database.
  • Firebase Analytics allows for unlimited number of hits. If you are using Google Analytics and want to reduce the volume of hits sent to your Google Analytics property, Firebase Analytics might be a solution for you!
  • With the Firebase Blaze plan, Firebase data can be retrieved with BigQuery. This allows for data to be exported out into whatever database or reporting tool you prefer to use.
  • If you use Firebase with Google Tag Manager, you get some other cool features. For example: the Firebase GTM containers also have Look Up Tables. The normal GTM containers do not have this feature yet. There are also more 3rd party tags available with Firebase GTM (Tune, AppsFlyers, etc).

If you are interested in some of these nice perks that come with Firebase Analytics, read on! The following is a high level approach on the migration from Google Analytics to Firebase Analytics.

What if you want to switch from Google Analytics to Firebase Analytics?

  • You need to install the Firebase SDK to your project. 
  • You need to create a Firebase instance to your project and wherever you’re making event calls to GA, you would add a new line of code to log an event to Firebase. These logEvent calls are nearly identical to GTM’s dataLayer push. This also means going back through your event parameters and making sure they abide by Firebase’s requirements. 
    1. Note that there is a 25 parameter limit to each custom event you create in Firebase.
    2. Each key has a limit of 24 characters and each value has a limit of 36 characters and can only contain alphanumeric characters and underscores (“_”), and must start with an alphabetic character.
  • Note: The Firebase Analytics data model is different than the Google Analytics data model. For example, screens do not exist in Firebase Analytics and there is no event category, action, and label. Understanding that the data model is different in Firebase Analytics is important to keep in mind before migration.

Depending on the amount of events you have, this may or may not be a lot of work. You may also notice that the Firebase UI can be very limited vs GA’s UI. This is where we see the limitations of Firebase vs Google Analytics.

Google Analytics: The Pros 

  • In Google Analytics, you can create custom reports, meaning you can slice and dice the data using different parameters you passed through. For example, you can create a category, action, and label for each event, and in GA’s UI, you can filter your data based on those parameters. In Firebase, although you can definitely send a category, action, and label through the event, you will not see that directly in the Firebase Analytics UI. Google Analytics is more customizable.
    • In order to see this in Firebase, you’ll need to use Big Query to see more detailed information.
  • GA has RealTime reporting.
  • Can rollup web and mobile users with the User ID feature.

You might be thinking, “That’s not really helpful….”

Now, that may all have been a lot of information and you might not be able to make your decision yet, so what should you do?

There is a middle ground to all of this. If you think you’d like to try out Firebase but not lose all of your abilities with Google Analytics, you do have a couple options:

  1. You could always download the Firebase SDK, log events using the Firebase instance and still use either the GA or GTM SDK to send data to GA. This would be using the Firebase SDK and GTM/GA SDK separately.
  2. If you don’t want extra code in your app, you could also use Firebase to push the events using the Firebase instance and use GTM to send those events to GA. This takes advantage of Firebase’s ability to integrate with the new version of GTM.
    • To do this, you do the same logEvent calls from the Firebase instance and then create a Universal Analytics tag in GTM that read from your keys (exactly like how a dataLayer push works) and send that info to GA.

In essence, you could have both Firebase Analytics and Google Analytics running at the same time. This might be best if you’re not so sure about Firebase Analytics, but you have the time to change some of your code in your project. At some point, this does seem where Google wants to go with mobile analytics, so eventually, you probably will want to switch to Firebase Analytics.

Do you have any questions about how to leverage Firebase or Google Analytics for your mobile app? Let us know!