Last updated: March 12, 2026

Kusuridoki ("we", "our", "the app") is a medication management application. We are committed to protecting your privacy and handling your data responsibly.

1. Information We Collect

We collect the following types of information:

• Account information: When you sign in with Apple or Google, we receive your name and email address (or Apple's private relay email). Anonymous sign-in collects no personal information.
• Medication data: Medication names, dosages, schedules, and adherence records you enter.
• Photos: Optional pill photos you take, stored locally with AES-256 encryption.
• Caregiver links: Connection data between patients and caregivers.
• Device information: Timezone, language preference, and push notification tokens for delivering reminders.

2. How We Use Your Information

• Deliver medication reminders and track adherence
• Sync your data across devices via Firebase Cloud Firestore
• Enable caregiver monitoring (only with your explicit consent)
• Generate adherence reports (PDF)
• Display personalized ads via Google AdMob (free tier)
• Monitor app stability and performance via crash reporting

3. Data Storage and Security

• Local data is encrypted using Hive with AES encryption
• Pill photos are encrypted with AES-256 before storage
• Cloud data is stored in Firebase (Google Cloud) with user-scoped security rules
• Firebase Storage files are protected by per-user access rules
• All network communication uses HTTPS

4. Data Sharing

We do not sell your personal data. Data is shared only in these cases:

• Caregivers: Medication status is shared with caregivers you explicitly link
• Google AdMob: Advertising identifiers for displaying ads (you can opt out via device settings)
• Firebase Analytics: Anonymized usage data for app improvement
• Sentry: Crash reports and performance data (health information is automatically removed before transmission — see Section 6)

5. Third-Party Services

The app uses the following third-party services:

• Firebase Authentication, Firestore, Cloud Functions, Cloud Messaging (Google)
• Google AdMob (advertising)
• Apple Sign-In (authentication)
• Sentry (crash reporting and performance monitoring)

Each service has its own privacy policy. Please refer to Google's Privacy Policy, Apple's Privacy Policy, and Sentry's Privacy Policy.

6. Crash Reporting & Performance Monitoring

We use Sentry (provided by Functional Software, Inc.) to monitor app stability and performance. When an error or crash occurs, the following data may be collected and transmitted to Sentry's servers:

• Crash reports: Stack traces, error messages, and app state at the time of the error
• Device information: Device model, operating system version, app version, and locale
• Performance data: App startup time, screen load duration, and transaction traces (sampled at 20%)
• Session replays: Anonymized screen recordings captured on 10% of error sessions, with all text and images masked by default
• User identifier: Your anonymous Firebase user ID only (no name or email)

What is NOT sent to Sentry: Medication names, dosages, pill colors, pill shapes, photos, or any other health-related information are automatically removed before transmission. We also strip personal information such as your name and email address.

Data is processed on Sentry's servers located in the United States. You cannot opt out of crash reporting separately, but you may stop all data collection by deleting your account and uninstalling the app.

7. Data Retention

• Local data: Stored on your device until you delete the app or clear app data. Encrypted with AES-256.
• Cloud data (if signed in): Stored in Firebase until you delete your account. Upon account deletion, all server-side data (medications, schedules, caregiver links) is permanently removed within 30 days.
• Crash reports: Retained by Sentry for 90 days, then automatically deleted.
• Analytics data: Retained by Firebase Analytics for 14 months in aggregated form, then automatically deleted.
• Ad consent preferences: Stored locally and reset upon app reinstallation.

8. Your Rights

• Access: View all your data within the app
• Export: Generate PDF reports of your adherence data
• Deletion: Delete your account from Settings. This permanently removes all server-side data including subcollections, caregiver links, and authentication records
• Revoke caregiver access: Remove linked caregivers at any time from Settings

These rights comply with Japan's Act on the Protection of Personal Information (APPI) and the EU General Data Protection Regulation (GDPR).

9. Children's Privacy

This app is not intended for children under 13. We do not knowingly collect data from children under 13. If you believe we have collected such data, please contact us.

10. Security Incident Response

In the event of a data breach that may affect your personal or health information, we will:

• Investigate and contain the incident within 72 hours of discovery
• Notify affected users via email (if available) and in-app notification
• Report to relevant authorities as required by applicable law (GDPR, APPI)
• Provide guidance on steps you can take to protect your data

To report a security concern, contact us at [email protected].

11. Changes to This Policy

We may update this policy from time to time. Changes will be posted on this page with an updated date. Continued use of the app after changes constitutes acceptance.