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.
api3.branch.io
classified as tracker · 2
Independent tracker databases attribute this domain to Branch Metrics, Inc. (Branch deep-linking/attribution), associated with data such as advertising ID, vendor/device/user IDs, local IP, CPU type — per TrackHAR (CC0).
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 medium — classification split: anthropic=tracker, openai=analytics, gemini=tracker. A human reviewed this domain's claims before anything here published.
Anthropic Claude — tracker
api3.branch.io is an API endpoint of Branch (Branch Metrics), a third-party mobile deep-linking and install-attribution SDK, which typically transmits device and identifier data to link app opens to marketing campaigns; it is not a Best Buy first-party domain. Since the app's label declares no data collection or sharing at all, this third-party attribution contact appears uncovered, though the exact fields sent cannot be confirmed from the given data.
OpenAI — analytics
api3.branch.io is a Branch domain commonly used for mobile attribution and deep-link analytics. The app declares no collection or sharing, so this contact appears undisclosed.
Google Gemini — tracker
api3.branch.io is operated by Branch Metrics, a mobile attribution and deep-linking tracking platform. Because the app declares no data collection or sharing, contacting this third-party tracking service appears undisclosed.
Apps measured contacting this domain
| App | Label gap | Donations | Contacts | Seen |
|---|---|---|---|---|
com.bestbuy.buyphone | not in label | 4 | 12 | 2026-07-28 → 2026-07-29 |
com.Payoneer.PayoneerDevAdHoc | — | 4 | 4 | 2026-07-28 → 2026-07-29 |
com.vanguard.app | — | 3 | 3 | 2026-07-30 |
The corpus grows one report at a time: donate your App Privacy Report — anonymous by design.
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Evidence and research improve when people push back. Tell us what to re-check — a misattributed domain, an outdated classification, a claim about your own app — and a human will review it. Responses can take up to 30 days.