Piece World · Privacy Policy

1. Who Processes Your Information

Piece World is operated by 北京澄笑科技有限公司. This policy explains how we process personal information when providing building-instruction browsing, digital building, accounts, favorites, completion records, and purchase entitlements, and how you can exercise your rights.

We process information lawfully, fairly, necessarily, and in good faith. This policy describes current features and does not use “including but not limited to” to encompass unlimited information collection. If we introduce new types of information, purposes, or processing methods, we will provide separate notice and obtain the relevant consent where required by law.

Email for privacy and account requests: piece_world@163.com.

2. Information We Actually Process

1. Sign in with Apple and Account Details

When: When you choose Sign in with Apple, restore sign-in, or use account features.
Information: The user identifier Apple provides to this app; a name and email address that may be returned during authorization (which may be an Apple hidden email address); email verification status; and identity tokens, one-time authorization codes, and related authorization credentials used to complete verification. We also generate an internal account identifier and record account creation, sign-in, and status changes.
Purpose: To create and identify accounts, display account details, maintain sign-in, verify authorization, and associate your purchase entitlements. If Apple does not return a name or email address, we will not, for that reason, separately ask you to provide identity documents or other real-name identification materials.

We do not receive your Apple password or obtain biometric information from Face ID or Touch ID. Apple performs the relevant system verification.

2. Account Security and Service Operation

When: When you sign in, access APIs, search for or download content, or when we handle irregularities and appeals.
Information: App version; device type (such as iPhone or iPad); IP addresses for sign-in and network requests; access times; request paths and necessary parameters (such as building-title search keywords, categories, or building identifiers); response or error information; and client information carried by network requests (such as User-Agent). This also includes session expiry, sign-out or revocation status, and necessary records of suspension or reinstatement reasons and times.
Purpose: To return requested content, maintain a single valid sign-in per account, prevent unlawful sharing or bypassing access controls, diagnose faults, safeguard service security, and handle appeals.

We do not use advertising identifiers for cross-app tracking or use search records to build advertising interest profiles. IP addresses are used for network communication and security handling, not to obtain precise location.

3. Favorites and Cloud Completion Records

When: When you add or remove favorites, or when a completed build needs to be synchronized with your account records.
Information: Your account identifier, the relevant building identifier, the time it was favorited, and the completed marker and completion time.
Purpose: To display My Favorites, completed-build counts, and building records, and to recognize the fact that your account has completed a build after you sign in again.

This does not mean uploading every step of your actions. Detailed steps, part positions, rotation angles, and operation history are not uploaded to our service cloud as unfinished building progress.

4. Purchases and Membership Entitlements

When: When you purchase, renew, or reverify entitlements, or when Apple notifies us of changes such as purchases, expiry, refunds, or revocations.
Information: Apple-signed purchase verification information and the information needed to verify and maintain entitlements: product, transaction, and original transaction identifiers; account association identifiers; purchase and renewal times; validity periods; refund or revocation status; auto-renewal status; billing retry or grace periods; and related information. Apple’s signed credentials may also contain verification fields specified by its transaction structure, such as purchase region and currency. Where applicable, we also record trial or gifted entitlements issued to an account.
Purpose: To identify purchase ownership, provide the correct membership or individual-building entitlements, prevent reuse of transactions, synchronize refund and expiry outcomes, and handle purchase disputes. The backend queries Apple for necessary current transaction or subscription status.

Apple processes payments. We do not obtain your bank card number, payment password, or payment verification codes.

5. Information You Provide When Contacting Us

When: When you send feedback, privacy requests, account deletion requests, copyright notices, or other questions to our contact email.
Information: The email address you use, your description of the issue, and any account information, screenshots, or attachments you voluntarily send that relate to the matter being handled.
Purpose: To respond to requests, carry out necessary identity verification, investigate problems, and resolve disputes. Do not send Apple passwords, payment passwords, verification codes, sign-in tokens, or sensitive materials unrelated to your request.

3. Information Stored Only on Your Device

The app locally stores detailed building progress, part positions and rotations, operation history, recent activity, necessary image and building-instruction caches, preferences, sign-in status, eligibility to continue the current build offline, and known account restrictions. Sign-in credentials are stored in the system keychain.

To investigate rendering and stability issues, the app also maintains size-limited local diagnostic logs. These may include runtime, building identifiers, steps, and memory or rendering status. The app does not automatically upload these local logs to our service servers. If you voluntarily submit diagnostic materials, or allow Apple to provide diagnostic information through system settings, the relevant materials will be used to address faults. We have not integrated third-party SDKs for automatic crash reporting or user behavior analytics.

Local files may be affected by your selected system backup settings. We do not currently provide cloud synchronization of unfinished building steps. Uninstalling the app, changing devices, or deleting local data may make local records unrecoverable.

4. Permissions, Tracking, and Web Pages

Current features do not request location, contacts, photo library, camera, or microphone permissions, and do not proactively read that content. Attaching a screenshot to an email yourself is different from the app automatically reading your photo library.

The app uses the network to load content, sign in, and verify entitlements. The locally available network status is used to retry connections. Disabling the network affects online services, but you may continue the current already-started build when the local resource and authorization requirements are met.

The app has no advertising or cross-app tracking SDKs and does not sell your personal information for advertising or marketing purposes. Home-page entry points such as continuing a build or viewing membership are shown according to account status as part of the service’s functionality; this is not the same as cross-service advertising tracking.

This policy and the Terms of Use are static web pages. They do not load advertising, third-party analytics scripts, or external fonts, and do not set advertising tracking cookies. If you choose to open an external link, that website provides its services under its own rules.

5. Third-Party Services and Necessary Transfers

We do not arbitrarily provide personal information to other companies. The following are the main services currently involved:

Apple system sign-in services (AuthenticationServices / Sign in with Apple): To verify an account, we exchange necessary authorization codes, tokens, and app identifiers with Apple. For how Apple itself processes account and device information, see Sign in with Apple & Privacy.
Apple purchase and subscription services (StoreKit, App Store Server API, and server notifications): These handle payments and purchase verification. We provide necessary transaction verification information to Apple and receive signed app-purchase, subscription-transaction and status information. An app-account association identifier is supplied only when signed in. Guests do not need to create a Piece World account to purchase. This does not give Apple your local part-operation history. Its services are subject to Apple’s Privacy Policy.
Alibaba Cloud servers and Object Storage Service (OSS): These host our service APIs, databases, building instructions, and image resources, providing necessary storage and network services. When requests are made to services hosted on Alibaba Cloud, necessary IP addresses, request paths, and client information are used for transmission, security, and operations. Service account data is processed on our behalf for hosting. Downloading building resources does not require uploading your detailed local building steps to Alibaba Cloud. See Alibaba Cloud’s privacy information.
NetEase 163 Mail: We receive requests you choose to send through the email address published on this page. The respective email service providers process email addresses, message content, and attachments when sending and receiving messages. The app itself has no NetEase Mail SDK.

ZIPFoundation, used in the app, is an open-source component for extracting building resources locally, not an advertising or analytics service. We do not use it to send personal information to the project’s maintainers.

We require processors acting on our behalf to process information only as necessary to provide the services and to take appropriate protective measures. In the event of legally required disclosure, or a merger, restructuring, or similar situation that may affect the entity processing information, we will fulfill the applicable duties to notify, protect, or obtain consent in accordance with law.

6. Storage Location, Retention, and Protection

Our primary service database and original OSS building-instruction and image resources are located in Alibaba Cloud’s Beijing region in mainland China. We also operate service API nodes in the western United States and distribute building instructions and images through a global CDN. Related processing may take place within and outside mainland China: depending on the access route, requests for sign-in, membership, favorites, and other service functions may be received and processed by the US node, and necessary network operation logs may be stored there. Building instructions and images may be cached on CDN nodes outside mainland China. When Sign in with Apple or purchase or subscription verification is used, necessary verification information is also sent to Apple’s service APIs; Apple’s processing locations are described in its privacy information. Where outbound-transfer notices, separate consent, or other procedures are legally required, we will fulfill those requirements.

Account and feature records: Retained for the life of the account and as necessary to provide the relevant services. After a valid deletion or account deletion request, information no longer needed will be deleted or anonymized in accordance with law.
Purchase, entitlement, and necessary security records: Retained only as needed for verification, dispute handling, or legally required retention periods. Any portion that must continue to be retained by law is restricted to the relevant purpose and is not used for unrelated purposes.
Contact and request records: Retained as needed to address the issue and resolve related disputes in accordance with law. Attachments you provide are not used for unrelated purposes.
Local data: Retained according to use of the app and device. Caches can be handled by the relevant clearing functions and may also be cleared by the operating system. Necessary local account restrictions are not lifted by ordinary image-cache clearing.

When information is no longer needed for its processing purpose and is no longer subject to statutory retention or dispute-handling requirements, we will delete or anonymize it. Data that cannot immediately be deleted from backups will be stored separately with processing restricted and handled under the backup update mechanism.

We protect information through measures such as HTTPS transmission and access controls. Relevant Apple authorization credentials are stored in encrypted form; app session credentials are stored as hashes on the server; and model resources are accessed through private storage and short-lived signed URLs. These measures do not mean all data uses the same form of encryption, nor can they guarantee absolute system security. If a personal information security incident occurs, we will take remedial action and fulfill notification and reporting duties as required by law.

7. Your Rights and Choices

Under law, you may request information about processing rules; access or copy your personal information; correct inaccurate information; request deletion or account deletion; withdraw authorization for consent-based processing; or exercise other personal information rights where applicable.

Please currently submit these requests to piece_world@163.com, describing the matter and the necessary information to locate your account. We conduct only identity checks proportionate to the risk, do not require unrelated sensitive information, and will complete verification and handling within 15 working days of receiving the request. If the law requires a shorter period, that period applies. If we cannot fulfill a request, we will explain the reasons and available remedies.

You can remove favorites, sign out, or clear caches in the app, and manage Sign in with Apple authorization and subscriptions in Apple’s system settings. Stopping Apple authorization, signing out, or uninstalling the app does not automatically delete all account and purchase records we lawfully retain. Please submit the relevant request if you want deletion or account deletion. Withdrawing consent does not affect lawful consent-based processing before withdrawal or necessary processing that may lawfully rely on other grounds.

Deleting a Piece World account does not automatically cancel an Apple auto-renewable subscription. If you no longer use it, also cancel renewal in Apple’s subscription management settings. Account restrictions or suspension do not prevent you from exercising personal information rights or submitting an appeal through the email address on this page.

8. Children and Minors: Special Rules for Children's Personal Information

Minors under 18 should use the service with guardian guidance and consent, and obtain guardian consent before purchases or subscriptions. This section sets out special processing rules for the personal information of children under 14 and applies together with the rest of this policy. Stricter requirements for children's information take precedence where applicable.

1. Information, Purposes, and Risks

Personal information of children under 14 is sensitive personal information. It may be processed lawfully only for a specific purpose, where sufficiently necessary, and with strict safeguards. Section 2 describes the information, processing circumstances, and purposes of the relevant features; Section 3 covers data on the device. A child's use of the service must not be used to expand collection or require information unrelated to the service. Exposure or misuse of account identifiers, network data, or usage records may allow a child's identity to be linked, intrude on their privacy, or harm their financial interests.

2. Notice to and Consent from Guardians

Before processing that legally requires guardian consent begins, guardians must receive prominent, clear information about the data categories, purposes, necessity, effects on the child's rights, retention periods and locations, safeguards, and ways to refuse, withdraw, correct, or delete, and give explicit consent. Separate consent must be obtained where required by law. Changes to purposes, methods, or data categories require renewed notice and consent as required by law. Refusing non-essential processing must not restrict unrelated features; declining information necessary for a particular feature may affect that feature.

The current app does not provide age identification, verifiable guardian consent, or a dedicated child-account process, and does not collect identity documents or dates of birth from all users to determine age.App Store content age ratings, Apple sign-in authorization, and purchase confirmation do not mean that we have obtained the guardian consent required to process children's information. Guardians should understand the relevant processing conditions before a child submits personal information. Reading this section or sending an inquiry email does not replace the required consent procedure.

3. Data Minimization and Strict Safeguards

Children's information must be used only for disclosed purposes with a lawful basis and retained no longer than necessary. Processing also requires a designated responsible person, minimum access privileges, access approval and records, encryption and other strict safeguards, and controls over and supervision of service providers. Providing, transferring, disclosing, or processing children's information across borders requires the applicable assessments, notices, consents, and other legal steps; broad authorization in this policy cannot replace them. These are requirements that must be met, not a statement that dedicated child-related processes that are currently unavailable have been implemented.

4. Rights of Children and Guardians

Children or their guardians may contact piece_world@163.com to request access, copies, correction, deletion, withdrawal of consent, or account handling. Describe the request and provide only the details necessary to locate the information; do not send passwords, verification codes, or unrelated identity documents. We will conduct identity and guardian-relationship checks proportionate to the risk of the request. As stated in Section 7, we will complete review and handling within 15 working days of receiving the request, or sooner where the law requires a shorter period or prompt action. Refusing or withdrawing consent to non-essential processing does not affect features that do not depend on that information.

5. Accidental Collection, Improper Authorization, and Security Incidents

If you discover that a child's information has been collected or used without legally required guardian consent or another lawful basis, notify us through the email address above. We will review the matter, stop processing that lacks a lawful basis, and promptly delete information that must be deleted by law. If retention is legally required or deletion is temporarily technically difficult, processing will be limited to necessary storage and security protection, and we will explain the outcome to the requester. We will not automatically close all services solely because a user is under 14. Security incidents involving children's information require prompt remedial action and notices to affected children and guardians and reports to authorities as required by law.

Additional age, guardian-consent, or children's-information requirements where a child is located must also be met. This policy does not represent that current features have completed the children's personal information compliance procedures of every jurisdiction.

9. Policy Updates and Contact

We will display this policy’s update and effective dates on this page. When important changes occur in processing purposes, information types, recipients, user rights, or similar matters, we will provide appropriate notice. Where renewed consent is legally required, we will seek it separately rather than substitute an unannounced page update.

Operator: 北京澄笑科技有限公司
Email for privacy and account requests: piece_world@163.com

You may also submit complaints or reports to the authorities responsible for personal information protection in accordance with law. This policy does not limit the rights granted to you by law.