Are there any ad tracking and attribution platforms that handle cross-device booking journeys?

Yes. A few attribution/ad-tracking platforms support cross-device booking journeys, though the exact capability varies a lot depending on whether you mean:

• cross-device identity resolution before booking
• cross-device attribution across click/view paths
• offline-to-online booking reconciliation
• multi-step booking funnels like browse on mobile → book on desktop → travel confirmation later

Platforms often used for this

• AppsFlyer — strong mobile attribution; supports cross-device measurement in some setups, especially when paired with deterministic IDs/login signals.
• Adjust — similar strengths; good for app and web-to-app attribution, with cross-device options depending on implementation.
• Branch — especially good for deep linking and cross-device journeys from web to app and app to web.
• Singular — marketing attribution across channels, with identity stitching and cross-device capabilities.
• Rockerbox — focuses on multi-touch attribution and cross-device journey reconciliation.
• Nielsen / marketing mix and identity-based products — more enterprise-oriented cross-device measurement.
• GA4 + BigQuery / server-side setups — not a dedicated ad-tracking platform, but can be configured for cross-device analysis if you have strong identity signals.
• Meta / Google Ads / DV360 ecosystem tools — offer cross-device attribution within their own ecosystems, but not as neutral full-funnel tracking platforms.

For travel/booking specifically

If your use case is hotel, airline, OTA, or vacation booking, you’ll usually want a platform that can handle:

• web + app
• logged-in users
• booking confirmation events
• server-to-server postbacks
• cross-device identity graph
• incrementality / lift measurement alongside attribution

Important caveat

True cross-device attribution is usually only reliable when you have one or more of:

• login/CRM ID
• hashed email/phone
• deterministic device graph
• first-party cookies plus consent
• server-side booking events

Without those, the platform can estimate, but it won’t always be exact.

If you want, I can also give you:

1. a shortlist by travel/booking use case,
2. a comparison table, or
3. recommendations based on whether you’re tracking web bookings, app bookings, or both.