What is cross-device continuity and its impact on measurement?

• A. Across all devices, identities are kept completely separate; the journey is measured independently per device.
• B. Cross-device continuity is not used in measurement.
• C. Cross-device continuity is about linking user identities across devices to understand the full journey and improves measurement accuracy.
• D. Cross-device continuity links user identities across devices to understand the full journey and improves attribution accuracy, but introduces privacy and identity resolution challenges.

Answer: (D)

Cross-device continuity means linking a user’s identities across different devices so you can see the full journey a person takes, from phone to tablet to desktop, rather than treating each device’s activity in isolation. When you can connect those touchpoints to the same person, you gain a clearer view of how actions on one device lead to actions on another, which makes attribution more accurate—you can better determine which sequences of devices and interactions contributed to a conversion.

This broader view improves measurement by reducing undercounting and confusion about where a conversion originated. It helps you understand the true path to purchase or engagement across devices, rather than assuming each device tells a separate story. At the same time, there are real challenges: matching identities across devices relies on probabilistic or deterministic methods that aren’t always precise, and it raises privacy and consent considerations. Privacy regulations, data governance, and user opt-ins affect what data can be linked and how confidently matches can be made, potentially impacting accuracy if matches are incomplete or disputed.

So, the best answer captures both the benefit—understanding the full journey across devices and improving attribution accuracy—and the practical caveats—privacy and identity resolution challenges that come with implementing cross-device continuity.