1. Scope and the personal-information processor

This policy applies to the EchoClass mobile app and to the account, live transcription, high-accuracy simultaneous interpretation, face-to-face translation, file transcription, AI summary, transcript management, membership and related services we provide through the app.

Personal-information processor: Beijing Xiaoyu Changxiang Technology Co., Ltd.

Email: xiaoyuchangxiang@163.com

In the app: EchoClass → Profile → Feedback

When you sign in or pay through a third party such as Apple, WeChat or Alipay, information that the third party processes as an independent personal-information processor is governed by the rules that third party gives you. Information we receive from a third party, or provide to a third party, is still handled under this policy.

2. How we collect and use your personal information

We follow the principles of lawfulness, legitimacy, necessity and good faith, and we process only the information needed for a clear function. Refusing optional information usually does not affect features that do not depend on it.

2.1 Information the app may collect

So you can quickly see what the EchoClass app may collect in different situations, we list it as “situation or purpose — personal information that may be collected.” We process the corresponding information only when you actually use that feature. We do not collect unrelated information merely because you install or open the app.

2.2 Audio and class content

Face-to-face translation records both people’s voices. Use it only when the other person knows.

A class photo may include a teacher’s or classmate’s portrait or personal information. Take photos only as needed for study, and follow the school’s and the class’s rules. We do not run face recognition on photos.

We do not extract a voiceprint from audio to identify a person, and we do not use your audio, video, transcripts, translations or AI summaries to train AI models, unless we separately and prominently tell you the specific purpose, scope and effect, and obtain the corresponding authorization as required by law.

2.3 Information we do not collect on our own

The basic features of EchoClass do not need your contacts, call history, SMS contents, precise location, calendar or health data. We will not refuse basic features because you deny an unrelated permission. If a later feature truly needs that information, we will update this explanation first and ask for permission in that specific situation. Device identifiers and similar data that a third-party analytics SDK may process are described in section 7.

3. Device permissions

You decide whether to grant a system permission. You can turn it off at any time in the device Settings. Turning it off affects only features that depend on it.

We do not use a permission request to obtain information unrelated to the current feature. The system may show slightly different permission names depending on the device, operating system and app-store rules.

4. On-device processing, cache and guest mode

1. To open faster and reduce lost content, the app may store transcription drafts, transcripts you have viewed, AI summaries, task status, playback progress, language preference and pending sync actions on the device.
2. Credentials such as sign-in tokens are stored in a system secure area such as the iOS Keychain or Android Keystore, not mixed with the ordinary transcript cache.
3. If you use guest mode, bind a phone number as soon as you can. Guest sign-in creates a guest account in the cloud. Your transcripts, documents and credits are kept on that account, and the account is linked only to a local identifier on the current device. Until you bind a phone number, uninstalling the app, clearing app data, or a damaged or replaced device means you cannot return to that guest account, and the records and credits in it cannot be recovered. Binding a phone number only adds that phone identity to the current account. Existing data is not affected. After binding, you can sign in with that phone number on another device and continue.
4. You can clear the corresponding local data by deleting a single record, clearing the cache, or uninstalling the app. Clearing the cache does not by itself delete account data already synced to the cloud. Manage cloud data by deleting it in the app or by deleting the account.

5. Cookies and similar technologies

The mobile app may use local storage, session tokens and on-device identifiers to keep you signed in, save preferences, prevent duplicate submissions and protect security. When a policy, payment or help page is opened inside the app, that page may use necessary cookies for the session and security checks.

6. Processors, sharing, transfer and public disclosure

6.1 Engaged processors and feature partners

To provide SMS, cloud storage, speech recognition, large models, payment and sign-in, we may engage vendors to process the information needed for a specific task. Only third-party SDKs that are actually embedded in the app are listed one by one in section 7. We agree in contract the purpose, period, method, types of information, safeguards, and each party’s rights and duties, and we supervise the processor. A vendor may not use the information for a purpose we did not entrust to it.

6.2 Third-party AI services

Transcription, translation, summaries and similar features are performed by third-party AI services. When you use them, our servers send the audio, files and text needed for that feature to the following vendors:

• Alibaba Cloud Computing Co., Ltd. (Alibaba Cloud Model Studio / Tongyi)
• Beijing Volcano Engine Technology Co., Ltd. (Volcano Ark, Doubao Speech)

What is sent to them does not include your phone number, nickname, account identifier, device identifier or location. As processors, the vendors may use this information only to return the corresponding result. They may not use it to train models or for other purposes.

Separate consent (iOS): before you use these features for the first time, the app tells you in a dialog which data will be sent to a third-party AI service. We send it only after you tap “Agree and turn on AI.” If you choose “Not now,” we do not send any data to those vendors. Viewing existing transcripts, and account and membership management, which do not depend on AI, are unaffected. To withdraw consent, delete the app (you will be asked again after you reinstall and use the feature again), or contact us as described in section 14. Withdrawal does not affect processing already completed.

6.3 Providing information to another processor

When we need to provide your personal information to an independent third party, we will, as required by law, tell you the recipient’s name, contact details, purpose, method and the types of information, and obtain your separate consent, unless the law provides otherwise. When you choose to sign in with Apple or WeChat, pay with WeChat or Alipay, or subscribe through the App Store, the third party you chose also processes the relevant information independently under its own rules.

6.4 Transfer

If personal information must be transferred because of a merger, division, restructuring, asset transfer, bankruptcy or liquidation, we will tell you the recipient’s name and contact details and require the recipient to remain bound by this policy. If the recipient changes the original purpose or method, it will obtain your consent again as required by law.

6.5 Public disclosure

We do not publicly disclose your personal information in principle. If disclosure is truly necessary, we will tell you the purpose, the types of information and the possible effect, and obtain separate consent as required by law, unless the law provides otherwise.

If you use a share link, the transcript, translation and AI summary of the class you choose are shown as a read-only web page to anyone who has the link (not the recording). This disclosure is started by you. We only create and provide that page on your instruction, and we record how many times the link is viewed so you can see it. You can revoke the link or set an expiry in the app at any time. The link stops working immediately when it is revoked or expires. It also stops working if you delete the record or delete your account. Share pages are not indexed by search engines. To stop illegal content being spread through a share link, before a link is created we automatically check the class title, transcript, translation and AI summary through the third-party AI services listed in section 6.2. Content that does not pass cannot be shared. If the content changes after it is shared, the original link stops, and creating a new one checks the content again. The review result is recorded so we can meet content-management duties required by law.

6.6 When separate consent is not required

We may process information without consent, as the law allows, where it is necessary to conclude or perform a contract to which you are a party, to meet a legal duty, to respond to a public-health emergency, to protect life, health or property in an emergency, or in other cases provided by law. We still follow purpose limitation and data minimization.

7. Third-party SDKs

To support WeChat sign-in, WeChat Pay, Alipay and app analytics on the client, EchoClass may integrate the following third-party software development kits (SDKs) in the Android and iOS apps. We list only third-party SDKs that are actually embedded in the client, may run on your device, and may process personal information.

8. Where we store information, and for how long

8.1 Where

In principle, personal information collected or generated in the mainland of the People’s Republic of China is stored on servers in the mainland. When you choose to use a service provided independently by an overseas entity, such as Sign in with Apple or the App Store, where that third party processes information is determined by its own rules. Other cross-border cases are handled under section 12.

8.2 How long

We keep your personal information only for the shortest time needed for the purpose, and then delete or anonymize it. Account information (phone number, links to third-party accounts, nickname and similar details) is kept while the account exists. After you delete the account, we delete or anonymize it within a reasonable time, except what the law requires us to keep or what is needed to handle a dispute. Data created by using the service (recordings and uploaded audio or video and their temporary copies, class photos, transcripts, translations, AI summaries and similar data) is kept until the processing is finished or you delete it. The original and translation from face-to-face translation are kept until you delete your account. Temporary copies made to complete processing are usually deleted within 7 days. Backup copies are usually rolled off within 30 days.

Data that the law requires us to keep (transaction and subscription records, network and security logs, support and feedback records, and similar records) is kept for the required period. For example, network and security logs are kept for at least 6 months, and transaction records for at least 3 years from the date the transaction is completed. They are deleted or anonymized when the period ends. An SMS code becomes invalid once verification finishes. Related sending and verification security records are kept for at most 6 months.

If the purpose has been achieved, cannot be achieved, or is no longer necessary, if you withdraw consent or delete your account, or if we stop providing the product and service, we will delete or anonymize personal information as required by law. If a legally required retention period has not ended, or deletion cannot be done immediately for technical reasons, we will stop processing other than storage and the security measures that are necessary.

9. How you manage personal information

To the extent applicable law provides, you may access, copy, correct, supplement or delete your personal information, withdraw consent, unlink a third-party account, delete your account, or ask us to explain the processing rules.

• View and correct: view or change your nickname, sign-in method and related settings in Profile. Transcript titles and records can be changed on their pages.
• Delete content: delete a single transcription record from the list. Deletion also affects the linked transcript, translation, AI summary, markers and class photos, unless the page says otherwise.
• Permissions and consent: turn off microphone, file or notification permissions in system settings, and turn off high-accuracy interpretation or cloud sync in the app. Withdrawal does not affect processing that was already done based on consent.
• Delete your account: submit a request under Profile → Account & security → Delete account. Deleting your EchoClass account does not cancel an Apple auto-renewing subscription. Cancel that separately in Apple’s subscription settings.
• Copy or transfer: use export to obtain a transcript. Where the legal conditions are met, you may email us to request a copy or transfer of other personal information.
• Object or restrict: if you believe processing is inaccurate, unnecessary or unlawful, you may ask us to correct, delete or restrict it, and you may complain to the competent authority.

If the app does not yet offer the relevant entry, email xiaoyuchangxiang@163.com. To protect the account, we may ask you to verify your identity. In principle we reply within 15 business days. For requests that are repeated, manifestly unreasonable, or may harm someone else’s lawful rights, we will explain the result and the reason as required by law.

10. How we protect your information

We take security measures suited to the risk, including encryption in transit, access control, least privilege, account isolation, audit logs, backup and recovery, secure storage of sensitive credentials, assessment of third-party services, and response to security incidents. Only people who need to know the information may access it, and they are required to keep it confidential.

No internet service is absolutely secure. Keep your device, verification codes and third-party accounts safe, and do not upload sensitive class content over a network you do not trust. If personal information is or may have been leaked, altered or lost, we will take remedial measures immediately and, as the law requires, report to the competent authority and tell you the type of incident, the possible consequences, the measures taken or to be taken, and suggestions for reducing the risk.

11. Personal information of minors

If you are under 18, read and use EchoClass under a guardian’s guidance. We do not mainly serve children under 14. If we identify that we need to process personal information of a child under 14, we will adopt specific rules, obtain the guardian’s consent, and apply strict safeguards.

If a guardian believes a minor provided personal information to us without consent, they may contact us using the details in this policy and ask for deletion or another request. When users record a class or upload a file, they should also take particular care not to collect or spread other minors’ voices and remarks beyond what is necessary.

12. Cross-border processing

Except where you choose to use a service provided independently by an overseas entity, such as Apple, or in other cases the law allows, we do not provide your class audio, transcripts, translations or AI summaries outside the mainland of the People’s Republic of China.

If our business later truly needs us to provide personal information to an overseas recipient, we will tell you in advance the recipient’s name, contact details, purpose, method, the types of information, and how you can exercise your rights. We will complete a data-export security assessment, a personal-information protection certification, a standard contract, or another applicable procedure, and obtain your separate consent when the law requires it.

13. Updates to this policy

We may update this policy when features, processing activities, third-party SDKs, or legal or regulatory requirements change. If there is a substantive change to the purpose or method of processing, the types of information, the retention period, device permissions, or what a third-party SDK collects and how it uses it, we will explain the update by a dialog, an in-app message, or another prominent method, and obtain your consent again when the law requires it.

We will not reduce the rights you have under this policy without your express consent. You can read and save this policy at any time under Profile → Privacy Policy.

14. Contact us

If you have a question, comment, complaint or report about this policy, the third-party SDK list, the security of your personal information, or a rights request, contact us as follows:

Personal-information processor: Beijing Xiaoyu Changxiang Technology Co., Ltd.

Email: xiaoyuchangxiang@163.com

In the app: EchoClass → Profile → Feedback

After we verify your identity, we will handle the request promptly, in principle within 15 business days. If you are not satisfied with the result, you may complain or report to the authority responsible for personal-information protection, or seek other remedies as the law allows.