Dengram Privacy Policy
Last updated: June 30, 2026 | Effective date: June 30, 2026
Dengram ("the App"), created by the solo developer kukuDev ("the Operator"), is a Markdown-based reading-notes app designed with data ownership and privacy as the top priority. The App has no sign-up or login, and core data such as your note content is stored only on your device. This policy explains what information the App processes and what it does not. By using the App, you agree to this policy.
1. Information Collected and Purpose of Use
The App does not create an account and does not collect personally identifying information such as your name, email, or phone number. Core data — note content, reading records, book and author information, and the images and results of sentences captured with the camera (OCR) — is stored only on your device and not transmitted externally (text recognition is also processed on your device).
Only the following minimal information is processed automatically to provide the service.
| Item processed | Processor | Purpose |
|---|---|---|
| Advertising identifier (Ad ID) | Google AdMob | Display banner ads and measure performance |
| Diagnostic and crash logs | Google Firebase Crashlytics | Diagnose and improve app stability |
| Purchase token and product ID | Google Play / verification server | Verify and restore the ad-removal in-app purchase |
| Book search term (title or ISBN) | External book search API | Retrieve book information (sent only during a search, discarded after up to 10 minutes) |
2. Sharing and Disclosure of Information
The Operator shares information only to the extent necessary to run the service, with the third parties below, and does not transmit your note content anywhere.
- Google AdMob: advertising-identifier processing and banner-ad delivery
- Google Firebase: crash-log processing, app-integrity verification, running the book-search proxy and purchase verification
- Google Play: in-app payment processing and receipt verification
- Google Drive: when you use backup, stored in your own account (the Operator does not retain it)
When you search for books, only the search term is sent to an external book API; no other personal information is transmitted. In addition, information may be transferred where required by law, where necessary to protect the Operator's rights or safety, or in connection with a business transfer (merger, acquisition, etc.).
3. Data Storage and Retention
Core data is stored only on your device. Notes are stored as Markdown (.md) files, and book and note metadata as an encrypted index (SQLCipher). When you uninstall the App, the data on the device is deleted with it. Deleted notes are kept in the trash for up to 30 days before being permanently deleted automatically; you can restore or permanently delete them beforehand. Google Drive backup data is stored in your own Drive and managed and deleted by you. The Operator does not retain your note content.
4. Data Security
On-device metadata is encrypted with SQLCipher, and encryption keys are kept in the operating system's secure storage (Android Keystore). External communications are encrypted with TLS/HTTPS, and server functions block abnormal requests with App Check. However, no method of transmission over the internet can be guaranteed to be 100% secure.
5. Your Rights
You can delete individual notes and books within the App; notes are permanently deleted after passing through the trash (30 days). You can reset the advertising identifier or opt out of personalized ads in your device settings. You can delete Google Drive backup data directly in your own Drive. The App has no accounts, so there is no separate account-withdrawal procedure.
6. Children's Privacy
The App is not intended for children under the age of 14, and we do not knowingly collect the personal information of children under 14.
7. International Data Transfer
Google (AdMob, Firebase, Play, Drive) and some book-information providers may process data on servers outside your country. By agreeing to this policy and using the App, you are deemed to consent to such transfers. The Operator takes reasonably necessary measures to ensure your data is handled securely.
8. Changes to This Policy
The Operator may update this policy from time to time. For significant changes, we will give notice at least 30 days before they take effect, for example through an in-app notice, and we ask you to check the "Last updated" date at the top periodically.
9. Contact
For questions about this Privacy Policy, please contact us at: