This Privacy Policy is issued by Nanjing Chunchun Technology Co., Ltd., the operator of Inkstone (the "App", "we", "us"). We understand how important your personal information is and collect and use it on a "minimum necessary" basis to provide the App's features. Please read this Policy in full before using the App. By using the App, you acknowledge that you have understood and agreed to this Policy.
We collect information only to the extent necessary to provide the features below. Apart from the email address required to register, most information is collected only when you actively use the corresponding feature.
| Permission / Information | Purpose | Required |
|---|---|---|
| Network access | Communicate with our servers, upload and sync | Yes |
| Storage / file access | Select and upload PDF, Anki and other files | When using upload |
| Vibration / haptics | Light feedback when flipping and rating cards | No, can be disabled in the system |
| Speaker / audio playback | Play the "correct answer" encouragement voice | No, can be disabled in the App |
The App does not collect your precise location, contacts, or your full photo library, does not read your messages or call logs, and does not include system-level push channels.
To provide core features, we entrust necessary information to the third parties below. We share only the minimum information needed for the corresponding feature and require them to protect it in accordance with law and contract.
| Third party / service | Information received | Purpose |
|---|---|---|
| Resend (email delivery) | Email address | Send sign-in verification codes |
| Google (Sign-in) | Google account identifier, email address | Account creation and sign-in |
| Apple (Sign in with Apple & In-App Purchase, iOS only) | Apple user identifier, purchase receipts | Sign-in and in-app purchases |
| RevenueCat (iOS only) | Purchase receipts, anonymous user identifier | Subscription / purchase status management |
| Alibaba Cloud DashScope (AI & OCR) | The text and page images you upload or paste | AI flashcard generation, "AI Explain", and text recognition (OCR) |
| Cloud hosting & object storage provider | Uploaded files, basic network and device information | File storage, media delivery, service hosting |
Except for the above, and except where required by law or necessary to protect the significant lawful interests of you or the public, we will not sell or rent your personal information to any third party.
To improve your experience and support offline study, the App caches deck cards, study progress, and necessary configuration locally on your device. You can clear this local data via "Clear cache" in the App or by uninstalling the App.
To the extent permitted by applicable data protection laws, you have the right to exercise the following over your personal information:
To exercise these rights, please contact us using the details at the end of this Policy. We will respond within 15 business days.
The App is intended primarily for adult users preparing for academic and professional exams and is not designed for children under 13. If you are a minor, please read this Policy with a guardian and use the App only with your guardian's consent. If we learn that we have collected a child's personal information without prior guardian consent, we will take steps to delete it as soon as possible.
We may revise this Policy from time to time. Material changes will be notified to you through in-app announcements or other prominent means. The updated Policy takes effect on the date it is published; your continued use constitutes acceptance of the revised Policy.
If you have any questions, comments, or complaints about this Policy or our handling of personal information, please contact: