Privacy Policy

Last updated: May 9, 2026 / Publisher: Satoshi Kutsuna

Satoshi Kutsuna ("we," "us," or "our") publishes the mobile application "ID Quick Reference" (the "Service"). This Privacy Policy explains how we handle personal information of users of the Service in accordance with applicable law.

1. Information we collect

The Service may obtain the following categories of information:

Category	Source	Examples
Subscription data	Apple App Store / Google Play Store via RevenueCat	Subscription status, purchase history, free-trial state. We do not receive your card number or full payment details.
Device information	Automatic from the app	Operating system, OS version, device identifier (advertising ID), app version.
Usage logs	Within the app	Chapters / topics opened, calculator usage, launch counts, session duration.
Antibiogram images (v2.0 onwards)	Voluntarily uploaded by the user inside the app	Antibiogram tables (PDF or photo) from the user's institution. For OCR / structured extraction, the image is transmitted briefly through our backend (Cloudflare Workers) to Anthropic's Claude Vision API. The transmitted image is expected to contain only aggregate facility-level susceptibility data — facility name, organism, antibiotic susceptibility — and must not contain patient identifiers, names, IDs, clinical narratives, or other protected health information (PHI). After processing, raw image data is not retained on our servers or by the API provider; only the structured result (organism × antibiotic susceptibility data) is stored locally on the user's device (localStorage).
Support correspondence	Email or contact form	Name, email address, message content.

2. Purposes

We use the information for:

Providing and operating the Service;
Verifying subscription state and processing billing;
Performing OCR / structured extraction of antibiogram images for the institutional-antibiogram feature (v2.0 onwards);
Improving the Service (bug fixing, new feature development, UX improvements);
Responding to user inquiries;
Communicating important notices about the Service;
Preventing abuse and unauthorised use;
Statistical analysis in a form that does not identify any individual.

3. Disclosure to third parties

We do not disclose user personal information to third parties except in the following cases:

With the user's consent;
As required by applicable law (e.g., a valid request from a court or law-enforcement agency);
To protect the life, body, or property of a person, where it is difficult to obtain the user's consent;
To service providers strictly to the extent necessary to operate the Service (payment platforms, cloud hosts, AI analysis APIs, analytics tools). Service providers are bound by confidentiality obligations.

4. External services we rely on

The Service uses the following external services. Each service is governed by its own privacy policy:

Service	Purpose	Privacy policy
Apple App Store / Google Play Store	App distribution, payment processing	Apple / Google privacy policies
RevenueCat	Subscription management	https://www.revenuecat.com/privacy
YouTube (embedded playback)	Video content (Paper Reviews tab)	Google privacy policy
Cloudflare Pages (content delivery)	Surveillance & news content delivery	https://www.cloudflare.com/privacypolicy/
Cloudflare Workers (antibiogram backend)	Relays antibiogram image data and verifies subscription state	https://www.cloudflare.com/privacypolicy/
Anthropic (Claude Vision API)	OCR / structured extraction of antibiogram images (only when the v2.0 institutional-antibiogram feature is used)	https://www.anthropic.com/legal/privacy
GitHub Pages (legal-document hosting)	Static page delivery	https://docs.github.com/site-policy/privacy-policies/github-general-privacy-statement

5. App Tracking Transparency (iOS)

The Service does not track users across other apps or websites. We do not collect or use the IDFA advertising identifier.

6. Cookies and similar technologies

The Service may use localStorage and similar device-side storage to remember user settings, bookmarks, and previously fetched content. These do not personally identify the user; they are used for service improvement and convenience.

7. Safeguards

We take reasonable and appropriate measures, including encryption in transit (HTTPS / TLS), to protect the information we hold against loss, leakage, or damage. For the institutional-antibiogram feature, image transmission is performed exclusively over HTTPS / TLS, and our contractual relationship with Anthropic confirms that data transmitted via the API is not used to train Anthropic's AI models. Our backend (Cloudflare Workers) does not retain the raw image after processing.

8. Retention

We retain personal information only for the period necessary to fulfil the purposes described in this Policy or as required by law, after which it is deleted. Subscription-related billing records are retained for the period required by applicable tax / accounting law (typically 7 years). Raw antibiogram image data is not retained on our servers or by the API provider once OCR processing has completed.

9. Access, correction, and deletion requests

Users may request access to, correction of, addition to, deletion of, or suspension of use of their personal information held by us. To exercise these rights:

Contact us at the email address shown below.
We may ask for information sufficient to verify your identity.
We aim to respond within a reasonable period (in principle, within two weeks).

10. Information from minors

The Service is intended for healthcare professionals and is not designed for use by minors. We do not intentionally collect personal information from children under 13 years of age (or the equivalent minimum age in the user's jurisdiction).

11. International transfers

Information may be processed in countries other than the user's country of residence (including the United States and the European Economic Area). Where applicable, we rely on appropriate safeguards (such as Standard Contractual Clauses) for such transfers.

12. Changes to this Policy

We may update this Policy as needed. The updated Policy takes effect when posted in the Service or on a related website.

13. Contact

For questions about how personal information is handled, please contact:
Privacy contact: Satoshi Kutsuna
Email: linezolid@mac.com