Privacy Policy
1. Controller
北京禹余科技有限公司 is the operator and personal information processor of DAYUMEMO and determines the purposes and means of processing personal information related to the app.
2. Information processed
- No email address or phone number is required to create a local notebook. When you enable cloud sync, the server binds the notebook identifier, authentication public key, and necessary device authorization information for authentication and synchronization.
- Device and synchronization information such as device name or identifier, IP address, platform, app version, login and sync times, and sync state.
- Encrypted notes, images and attachments that you choose to store or synchronize.
- Operational and security logs containing request status, errors and abuse-prevention events.
- Local session cookies or storage used for login state, agreement acceptance, preferences and security state.
- For self-hosted sponsored cards: platform, language and the network information inherently required to deliver the configuration request. No mobile advertising identifier is requested.
3. Purposes and legal bases
Information is processed to provide accounts, encrypted storage, editing, migration, synchronization, export, security and support; to comply with legal obligations; and, where consent is required, to enable optional permissions or third-party advertising technology. The first advertising phase uses contextual, non-personalized sponsored cards delivered by the service operated for DAYUMEMO.
4. Encryption
Note content is encrypted on the client before cloud synchronization. The service is designed not to possess the plaintext data key required to read synchronized content. You remain responsible for protecting devices, passwords and recovery material.
5. Advertising
A non-empty note list may show one sponsored card selected without behavioral profiles. Display position, campaign dates and eligible platforms can be changed remotely. The client enforces a maximum of one feed ad and displays no feed ad when there are no notes. Interstitial capability is reserved and disabled by default.
If a third-party advertising SDK is introduced, this policy and the third-party disclosure list will be updated before activation. The provider, data fields, retention, transfers and opt-out method will be disclosed. In regions requiring consent, the SDK will not initialize until the required choice is obtained.
6. Sharing and processors
Personal information is not sold. Necessary service providers may process limited information under contractual safeguards. Information can also be disclosed where legally required or necessary to protect users and the service. A current third-party list will be published before any independent advertising SDK is enabled.
7. Retention and transfers
- Local notes: Notes remain on your device until deletion, clearing app data, or uninstallation. Uninstallation, loss of a device, or loss of keys may prevent recovery. Complete migration or keep an independent backup first.
- Encrypted hot-sync payloads: Ordinary relay payloads are retained for up to 30 days from server receipt and may be deleted earlier after all target devices acknowledge receipt, when no recipients remain, or under capacity cleanup rules. This is not permanent backup and does not guarantee a complete notebook or history. The 90-day device activity window is not a note retention period.
- Temporary full migration: A migration window is valid for up to 24 hours; the actual expiry is shown in the app. Expiry, cancellation, or completion starts the cleanup process. Migration storage is not long-term backup.
- Identity and sync metadata: Notebook identifiers, authentication public keys, device authorizations, and necessary commit-chain information are retained while cloud service is enabled only as needed for authentication, device management, and sync verification. After cloud identity deletion or termination, information no longer needed for ordinary service is deleted or anonymized, subject to applicable security-audit and legal preservation requirements.
- Network security logs: Relevant network logs subject to statutory retention are kept for at least six months. Other diagnostic logs are retained only until necessary troubleshooting is complete. Logs should not contain note bodies, attachment contents, passwords, data keys, or complete authentication credentials. Log retention is separate from note ciphertext retention.
- Feedback and third-party information: Feedback is retained until handling and necessary verification are complete, then deleted or anonymized unless law requires otherwise. Actual third-party processing and retention periods are disclosed before enabling the relevant service.
Turning off sync does not delete cloud data or automatically disable sync on other devices. Cloud deletion does not itself remove local notes. Where statutory retention applies or immediate removal from backups is technically impracticable, processing other than storage and necessary security protection stops, and cleanup follows legal requirements or backup rotation procedures.
Lawful Disclosure and Data Preservation
When a competent authority lawfully requests disclosure or preservation, we verify its authority, legal basis, and scope. We provide only information lawfully requested and actually retained, including ciphertext and relevant metadata, and explain applicable encryption and technical limitations. Data never uploaded or already deleted cannot be recreated on demand.
Content in newly created notebooks is encrypted on the device. The sync service and new-notebook activation endpoints do not receive plaintext data keys or private keys used for decryption. This statement does not cover plaintext feedback or ordinary exports and is not a blanket assurance about all cloud materials from historical versions.
Existing information subject to a valid preservation requirement must be excluded from ordinary expiry, capacity, and account-deletion cleanup, with access and use restricted. Preservation does not automatically determine whether future data is received or sync is suspended: the scope of future data and continued receipt or service restrictions follow the specific legal requirement. After release, deletion is reassessed under the original retention rules and applicable law; the ordinary 30-day period does not restart. Preservation is not a long-term backup service.
Information is retained only as long as needed for the stated purpose, legal obligations and security. Deleted or closed-account data is removed or anonymized, subject to limited backup and legal-retention periods. Cross-border processing will be disclosed and handled under the safeguards required by the destination and origin jurisdictions.
8. Your choices and rights
Depending on your location, you may request access, correction, export, deletion, restriction, objection, consent withdrawal or a copy of your information. You may also request account deletion. Contact admin@getdayu.cn; we may verify account ownership before acting.
9. Children
DAYUMEMO is not currently offered for registration by children under 14 and is not directed to children under 13. We do not knowingly use children's personal information for advertising. A verifiable parental-consent process must be introduced before opening the service to younger users.
10. Security incidents and updates
Reasonable technical and organizational safeguards are used. Where required, affected users and authorities will be notified of qualifying incidents. Material policy changes will be presented prominently, and renewed consent will be requested when the law requires it.