Which of the following is a challenge in cross-app and web measurement?

• A. There are no limitations in insight into user journeys.
• B. Web attribution is fairly advanced, while app attribution is mostly still 'last click'.
• C. App attribution is flawless across all channels.
• D. Users often have multiple touchpoints across multiple channels prior to conversion.

Answer: (D)

Cross-channel, cross-device attribution is the core difficulty here. Measuring a single user’s journey across web and apps, across different devices, requires stitching together scattered data and deciding how much credit each touchpoint deserves. People interact with multiple channels before converting, so you can’t rely on a simple path or a single source of truth. Privacy limits, evolving identifiers, and the absence of a universal user ID make it hard to deterministically link every interaction to the same person, which is why modeling and identity resolution are needed. That’s why the statement about users having multiple touchpoints across multiple channels before conversion best describes the challenge. The other options misstate the reality: there are limitations in visibility, app attribution isn’t flawless across all channels, and web attribution isn’t universally “advanced” compared to app attribution.