Shanghai Zhuqu Technology Co., Ltd. 中文

Privacy Policy

Last updated: 【待填写：更新日期】 · Effective date: 【待填写：生效日期】

Draft — subject to legal review. This policy is based on the app's current implementation and plans, and will be revised according to its actual features and legal advice before launch. This English version is for reference; if it differs from the Chinese version, the Chinese version prevails.

Shanghai Zhuqu Technology Co., Ltd. ("we", "us") understands how important your personal information is to you. This policy applies to our violin practice app 弦动 (the "App") and to this website (vchord.app). Please read it carefully before using our services, especially the parts in bold.

  1. Information we collect
  2. How we use your information
  3. Processors, sharing and disclosure
  4. Where and how long we store your information
  5. How we protect your information
  6. Accessing, correcting and deleting your information, and deleting your account
  7. Children
  8. Changes to this policy
  9. Contact us

1. Information we collect

We follow the principles of lawfulness, legitimacy, necessity and good faith, and collect only the information needed to provide our services. You can use the App's on-device features as a local guest without signing in; in that case we do not collect any account information.

1.1 Information processed only on your device

  • Microphone audio: analyzed in real time on your device to follow your place in the score and judge intonation and rhythm. It is never uploaded to our servers.
  • Practice recordings and history: stored only on your device by default and never uploaded automatically.
  • Practice settings and tuning results: stored on your device.

1.2 Sign-up and sign-in

  • Email account: your email address and password. Passwords are stored only as salted Argon2 hashes, so we never know your actual password. We send emails to verify your address, recover your password and confirm email changes.
  • Planned sign-in methods (not yet available; apply once launched): phone number with an SMS code, for which we will collect your phone number and send codes to it; and Sign in with Apple, for which we will receive the user identifier provided by Apple and the name and email address you choose to share (possibly an Apple relay address). We never receive your Apple ID password. 【待填写：确认手机号、Apple 登录的上线时间（英文）】

1.3 Information generated when you use online features

  • Cloud library: the scores, revisions and collections you sync, upload or share, and your cloud storage usage. Scores on your device are uploaded only when you choose to sync them, add them to a collection, or confirm the upload when sharing.
  • Score recognition: images or PDFs are uploaded for recognition only when you take a photo or choose a file and start recognition. By default, the original file is kept for 30 days after the task finishes so you can compare while proofreading, and counts toward your cloud storage. You can turn off "Keep recognition originals for 30 days" in Me > Privacy and data; new tasks then keep the original only while recognition runs.
  • Sharing: when you share a score or collection, the recipient receives a copy of it as it was at that moment.
  • Service logs: IP address, access time, request records and errors generated when you access our servers, used to keep accounts and services secure and to troubleshoot.

1.4 Device permissions

  • Microphone: captures your violin playing for real-time intonation and rhythm feedback.
  • Camera: takes photos of sheet music for recognition into editable scores.
  • Photos: lets you choose photos of sheet music for recognition into editable scores.

Each permission is requested only when you use the related feature. You can turn them off at any time in your iPhone's Settings without affecting other features.

1.5 This website

This website has no sign-up, uses no cookies and no third-party analytics. This website is currently hosted by Cloudflare, a provider outside mainland China. When you visit, Cloudflare processes and logs your IP address, access time, the page requested and browser type for content delivery, security and troubleshooting.

2. How we use your information

  • To create and manage your account, verify your sign-in and send account-related emails;
  • To provide cloud sync, sharing and score recognition;
  • To keep accounts and services secure and to detect and prevent fraud and attacks;
  • To handle your questions, feedback and complaints;
  • To meet our legal obligations.

We will ask for your consent before using your information for any purpose not described in this policy. We do not sell your personal information or use it for advertising.

3. Processors, sharing and disclosure

We do not sell or rent your personal information. The App currently includes no third-party analytics or advertising SDKs. We share necessary information only in the following cases:

  • Email delivery: to send verification, password recovery and other account emails, we pass your email address and the message to our email provider (【待填写：正式环境邮件服务商名称（英文）】).
  • When you share: recipients can see the scores or collections you share with them.
  • Legal requirements: when required by law, legal proceedings or mandatory requests from government authorities.

If we add third-party SDKs or new kinds of sharing, we will update this policy and list each SDK's name, provider, purpose and the information it collects.

We do not publicly disclose your personal information unless required by law.

4. Where and how long we store your information

  • Location: personal information collected and generated within the People's Republic of China is stored on servers located in mainland China. We do not proactively transfer your personal information outside China; if such a transfer becomes necessary, we will inform you and obtain your separate consent as required by law.
  • Retention: account information and your cloud library are kept while your account exists; recognition originals are kept for 30 days after the task by default. After you delete your account, online data is deleted within 24 hours, and backups are deleted automatically after at most 30 days. To prevent a deleted account from coming back if an old backup is restored, we keep a minimal deletion record that contains no email address or credentials. Other periods apply where the law requires (for example, network logs must be kept for at least six months).

5. How we protect your information

  • Data between the App and our servers is encrypted in transit with HTTPS;
  • Passwords are stored as salted Argon2 hashes, and sign-in tokens are kept in the device's system keychain;
  • Each account's data is strictly isolated, and only authorized staff can access personal information;
  • If a security incident involving personal information occurs, we will notify you and report to the authorities as required by law.

6. Accessing, correcting and deleting your information, and deleting your account

  • Access: the Me tab shows your account email, cloud storage and on-device data; Me > Privacy and data explains how the App handles data.
  • Copy: use Me > Local backup to export the scores, drafts, practice records and settings on your device. For a copy of other personal information, email us.
  • Correction: change your password or email in Me > Account.
  • Deletion: you can delete scores and practice recordings in the App, and where provided by law you can ask us to delete your personal information.
  • Withdrawing consent: turn off microphone, camera or photo access in your iPhone's Settings, turn off "Keep recognition originals for 30 days", or delete your account. This does not affect processing already carried out based on your consent.
  • Deleting your account: in Me > Account, choose "Delete account", enter your password again and confirm, or request deletion by email. The account is disabled immediately, every device is signed out, and this account's scores, drafts, recordings and settings are removed from the device. Online data is deleted within 24 hours and backups are kept for at most 30 days. Deletion cannot be undone; signing up again with the same email does not restore any data.

For requests made by email, we may need to verify your identity first for security, and will respond within 15 working days after verification.

7. Children

If you are under 14, please read this policy with your parent or guardian and create an account or use online features only with their consent. If we learn that we have collected personal information from a child under 14 without prior parental consent, we will delete it as soon as possible.

8. Changes to this policy

We may update this policy from time to time. Updated versions will be published in the App and on this website, and we will notify you prominently (for example, with an in-app notice) of significant changes.

9. Contact us

Company
Shanghai Zhuqu Technology Co., Ltd.
Address
Room 103, Building 1, No. 245 Jiachuan Road, Xuhui District, Shanghai, China
Email
admin@zhuqutech.com
Personal information protection contact
【待填写：个人信息保护负责人联系方式】

If you are not satisfied with our response, you may also file a complaint with the relevant regulators, such as the cyberspace, telecommunications or public security authorities.