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.
mail-api.proton.me
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
mail-api.proton.me is on proton.me, the app publisher's own domain, and appears to be the Proton Mail backend API the client necessarily contacts to send and receive mail. First-party service traffic of this kind is covered by the app's declared collection categories (account details, contacts, diagnostics), so nothing here implies an undisclosed data flow.
OpenAI — first-party
The domain mail-api.proton.me appears to be Proton's own mail API endpoint and is consistent with core app functionality. The provided privacy label declares several relevant data categories, and the contact alone does not establish an undeclared data flow.
Google Gemini — first-party
The domain mail-api.proton.me is an official backend API endpoint operated by Proton for the Proton Mail application, making it a first-party contact. First-party communication for core app functionality does not constitute undisclosed third-party data sharing.
Apps measured contacting this domain
| App | Label gap | Donations | Contacts | Seen |
|---|---|---|---|---|
| Proton Mail: Encrypted Email | — | 3 | 642 | 2026-07-30 |
The corpus grows one report at a time: donate your App Privacy Report — anonymous by design.
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