Yes, Google Analytics 4 (GA4) allows you to track user interactions across multiple websites and apps using a system called ‘User-ID’ and, increasingly, through Google Signals. This cross-platform tracking relies on identifying users consistently, rather than solely relying on browser cookies.
As of December 2025, GA4’s User-ID feature enables you to create a unique, persistent identifier for each logged-in user. When a user logs into your website *and* your app (or multiple websites you own), GA4 can associate their activity under that single User-ID. Google Signals, activated within GA4, uses Google-signed-in user data (where users have ad personalisation enabled) to provide aggregated and anonymised cross-device reporting. Currently, Google Signals is subject to data thresholds and may not be available for all Australian businesses due to privacy regulations and user base size. GA4 now includes enhanced measurement, automatically tracking events like page views, scrolls, outbound clicks, site search, video engagement and file downloads, across both web and app properties. Data residency options, important for Australian compliance with the Privacy Act 1988, allow you to specify where your GA4 data is stored. In 2026, Google is expected to further integrate GA4 with its Customer Match service, potentially offering more granular cross-platform audience building capabilities.
Ultimately, GA4’s cross-platform tracking functions by linking user activity to a consistent identifier, providing a unified view of the customer journey across your digital properties.
