At the center of the Google Analytics 4 data model are events and event parameters. Most aspects of collecting data for Google Analytics 4 are event based and also usually include parameters.
The articles in this section review considerations around events that are essential for your transition from Universal Analytics to Google Analytics 4.
Let’s start with a review of tracking in Universal Analytics.
Universal Analytics data collection model
In Universal Analytics, the basic unit of collected data is referred to as a hit. A hit is essentially a package of descriptors that is sent to the Analytics servers to record a user interaction.
The two most commonly used hit types in Universal Analytics are pageviews and events. The default tracking snippet (either gtag.js or analytics.js) automatically sends a pageview hit. Google Tag Manager provides a default tag type of Google Analytics: Universal Analytics, which in turn provides a default track type of Page View.
For most other user interactions that you want to record in Universal Analytics (e.g., video views, file downloads, or widget clicks) you need to generate an event. If you’ve implemented event tracking in Universal Analytics, you’re likely familiar with the three descriptors you can use for an interaction: event category (such as video), event action (such as progress), and event label (such as 75%).
In addition to these designated fields, you can include additional descriptors in the form of custom dimensions and values, such as the custom dimension video type with values of corporate, educational, or promotional.
Google Analytics 4 data collection model
Google Analytics 4 is based on a different kind of event and offers a more flexible and agnostic data collection paradigm that has its origins in Google Analytics for Firebase.
Firebase origins
Firebase is a suite of services designed to facilitate the development and marketing of Android and iOS mobile apps. One of the pillars of Firebase is Google Analytics for Firebase, known more commonly as Firebase Analytics, which lets you measure app performance and create audiences for app marketing, targeting, and optimization.
Since a pageview is not relevant in the context of mobile apps, Firebase Analytics, from the beginning, has been based on the event and event-parameter paradigm. For that same video interaction tracked in Universal Analytics with event category, event action, and event label, you might use a video_progress event, with video_title and video_percent as the event parameters, for tracking in Firebase Analytics.
Integrated reporting across websites and apps
Google Analytics 4 uses the same event and event-parameter paradigm that originated in Firebase Analytics.
If you’re already tracking your Android or iOS app with Firebase, you can instantly sync your Firebase project with a Google Analytics 4 property. You don’t have to configure new tracking in your mobile apps (unless, of course, you want to track additional interactions or taxonomy).
The migration to Google Analytics 4 for websites consists largely of recreating your existing Universal Analytics tracking — in some cases through automation and in other cases manually — so that it collects data for the Firebase/Google Analytics 4 schema.
The exercise of mapping your Universal Analytics tracking to Google Analytics 4 can provide multiple benefits:
- More meaningful data: The Google Analytics 4 schema is more inherently meaningful since each parameter is named according to its specific function (rather than the more generic event dimensions in Universal Analytics).
- More flexibility in describing data: With up to 25 parameters (including event_name), you can describe each interaction with greater flexibility.
- A single taxonomy: You can use identical tracking taxonomies in your web, Android, and iOS data streams to support meaningful and cohesive cross-platform reporting in Google Analytics 4.
See the next article in this section for more detailed information about Mapping Universal Analytics to Google Analytics 4.