GA4 100 Questions (Part 1): Concepts, Benefits, and Why You Should Upgrade

Part 1: Basic Concepts

Q 1.1: What is GA4?
Answer: Google Analytics 4 (GA4) is Google's next-generation Web/App analytics tool launched in 2020. It uses an event-based data model. We recommend all users switch to GA4 immediately to begin building historical data.

Q 1.2: What is UA (Universal Analytics)?
Answer: Universal Analytics is the previous generation of GA. The standard version will stop collecting data on July 1, 2023, and the paid 360 version will sunset on July 1, 2024. Migrating to GA4 is urgent.

Q 1.3: What is a Property?
Answer: A "Property" is a data bucket that holds data for a website or app. If a client has 3 distinct brands, they should create 3 separate Properties.

Q 1.4: What is a Data Stream?
Answer: A new concept in GA4, a Data Stream sits inside a Property. Best practice is to have three streams per Property: one for Web, one for iOS, and one for Android. Each stream has a unique Measurement ID (starting with G-) for tagging.

Q 1.5: What is Firebase and GA4F?
Answer: Firebase is Google's app development platform. "Google Analytics for Firebase" (GA4F) is the SDK used to track app data. To see app data in GA4, you must install the GA4F SDK.

Part 2: Why Upgrade to GA4?

Q 2.1: What is Cross-Channel Measurement?
Answer: GA4 excels at viewing the full picture—Paid, Owned, and Earned media. By linking Google Ads and using UTM parameters for non-Google traffic, GA4 unifies traffic sources. Plus, enabling Google Signals allows for true cross-device analysis.

Q 2.2: What are the benefits for Ad Optimization?
Answer:

1. Faster Learning: Pass "shallow" conversion events (like dwell time) to ad platforms for faster algorithm learning.

2. Audience Activation: Segment users deeply (e.g., predicted top spenders) and share these lists with Google Ads for remarketing.

3. App Integration: Access features like tROAS bidding for Android apps.

Q 2.3: Key Differences: GA4 vs. UA
Answer: The core difference is the data model. UA was session-based; GA4 is event-based. This allows GA4 to unify Web and App data in a single view for the first time. It also introduces AI-driven features like predictive audiences and natural language insights.