Kangji
About this app
Kangji is a privacy-first personal health record. You can store and analyze medical images (X-rays, lab reports, prescriptions) entirely on your device. AI vision analysis runs through a secure cloud endpoint — the image is sent for analysis, then deleted within 24 hours.
Privacy Policy
This policy describes what Kangji collects and how we use it.
Data we collect
| Data | Linkage | Used for |
|---|---|---|
| Medical images | Linked to you, stored on device only | Stored in an encrypted SQLCipher database on your iPhone. Sent to a Google Cloud Run endpoint only when you request AI analysis; deleted from our servers within 24 hours. |
| Analysis results | Linked to you, stored on device only | AI-generated text describing the image, stored locally in the encrypted database. |
| Anonymous error logs | Not linked to you | PII-redacted error reports to diagnose crashes. |
Third-party services
Kangji relies on these services to function. Each is bound by its own privacy policy.
- Google Cloud Run (kangji-vision-analyze). Receives medical images for AI analysis. Images are processed and deleted within 24 hours. The endpoint enforces request rate limits per device.
- Alibaba Qwen-VL and Google Gemini Vision APIs. Underlying AI models that analyze the image. We send no other personal info — no user ID, no demographic data.
AI processing
Kangji sends some of your content to an AI model for processing. The AI provider receives only the content needed for the task — not your user ID, email, or any other personal identifier. We do not use your content to train any model.
Tracking
Kangji does not track you across other apps or websites. We do not share data with advertising networks, analytics platforms used for cross-app profiling, or data brokers.
Your rights
- Access — request a copy of your data by emailing us.
- Delete — see Delete Account below.
- Correct — edit your profile in the app, or email us for help.
- Object — opt out of optional features in iOS Settings.
Data retention
We retain your data as long as your account exists. After you delete your account, all personal data is permanently removed within 30 days. Anonymous diagnostics may be retained longer in aggregated form.
Children's privacy
Kangji is not directed at children under 13. We do not knowingly collect data from children under 13. If you believe we have, contact us and we will delete it.
Changes to this policy
If we change this policy materially, we will notify you in the app and update the date at the bottom of this page.
Contact about privacy
Email support@cyohei.net with any privacy question.
Terms of Use
By using Kangji, you agree to these terms.
License
cyohei grants you a personal, non-exclusive, non-transferable license to use Kangji on Apple-branded devices that you own or control, per the App Store Terms of Service.
Acceptable use
- Do not reverse engineer, decompile, or attempt to extract source code.
- Do not use the app to violate any law or third-party right.
- Do not abuse the service (e.g. automated scripts hammering the API, attempts to exceed your quota).
- Do not impersonate someone else or misrepresent your identity.
Your content
You retain all rights to content you create in Kangji (recordings, notes, scores, favorites). You grant us a limited license to store and process that content solely to operate the app for you.
Disclaimer of warranties
Kangji is provided as is, without warranties of any kind. We do not guarantee uninterrupted, error-free, or perfectly accurate output (especially AI-generated content).
Limitation of liability
To the maximum extent permitted by law, cyohei is not liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of Kangji.
Governing law
These terms are governed by the laws of Japan, without regard to its conflict of laws principles.
Termination
We may suspend or terminate access if you violate these terms. You may stop using Kangji and delete your account at any time.
Support
Need help? Email support@cyohei.net. We aim to respond within 2 business days.
Before you email
- Make sure you're on the latest version of the app (App Store → your profile → check for updates).
- Try restarting the app and your device.
- If the issue is account-related, include your sign-in email so we can find your account.
Bug reports and feature requests
Email support@cyohei.net with a screenshot or short description. We read every message.
Delete Account
You can permanently delete your Kangji account and all associated data at any time.
From the app
- Open Kangji.
- Go to Settings → Account → Delete Account.
- Confirm. Your account and data are queued for deletion immediately.
From this website
If you cannot reach the in-app option, email support@cyohei.net from the email address registered to your account, with the subject Delete my kangji account. We will verify ownership and delete the account within 7 days.
What gets deleted
- Your Firebase Auth identity (email, sign-in method).
- All your content stored in Firestore and Firebase Storage.
- Subscription receipts (we keep aggregate financial records as required by law, but they are no longer linked to your identity).
What does not get deleted automatically
- Apple subscriptions — to stop billing, you must also cancel the subscription in your Apple ID settings.
- Local data on your device — deleting the app from your device removes it.
After 30 days, deletion is permanent and irreversible.