This page aggregates measured, corroborated evidence: donors' iPhones recorded apps contacting this domain, every claim below was reported by separate accepted donations and published under a human verdict (later rows for an approved app inherit its verdict). A contact is a measurement, not an accusation — it does not show what data was sent.
auth.trivago.com
classified as first-party · 2
What our research panel found AI-drafted · human-reviewed
We ask several independent AI models the same question and publish their answers separately — cross-vendor agreement is evidence against fabrication, and disagreement is worth seeing. 3 of 3 models answered, overall confidence high. A human reviewed this domain's claims before anything here published.
Anthropic Claude — first-party
auth.trivago.com is a subdomain of the app publisher's own domain (trivago) and the hostname suggests an authentication/login endpoint, making it first-party infrastructure rather than a third-party tracker. The app's label already declares collecting Name, Email address, and User IDs, which covers the data flow an authentication endpoint would imply.
OpenAI — first-party
The auth.trivago.com subdomain appears to be a first-party authentication endpoint for trivago. The app declares collection and sharing of identifiers, account information, and related usage data, so this contact is not clearly outside the label.
Google Gemini — first-party
auth.trivago.com is a first-party domain owned by Trivago used for authentication services. This routine first-party operational traffic is consistent with the app's functionality and declared user ID collection.
Apps measured contacting this domain
| App | Label gap | Donations | Contacts | Seen |
|---|---|---|---|---|
| trivago: Compare hotel prices | — | 4 | 8 | 2026-07-28 → 2026-07-29 |
The corpus grows one report at a time: donate your App Privacy Report — anonymous by design.
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