Zhiyu privacy policy

Applies to Zhiyu 0.1.1 for Android, macOS and Windows, and the iOS/iPadOS 0.1.0 candidate (not publicly available). Revised 30 September 2026. Operator: Martell. Privacy contact: k34ubll5@gmail.com.

Communication between devices

Zhiyu requires no service account. After you compare security codes and confirm pairing, text, images, files and transfer information such as file names, sizes and checksums go to the peer device you select. The local network supports text and files; Bluetooth supports short text and receipts, not files. We do not provide a public content feed, user-content hosting or cross-network relay service.

Discovery and device identity

Nearby discovery uses temporary identifiers, service identifiers, ports and reconnection locators. Participating devices on the local network can observe source IP addresses. Bluetooth discovery uses service UUIDs and system Bluetooth identifiers and may read a peer’s temporary reconnection hint. Authenticated connections exchange device names, app device identities and public-key information; pairing records are stored locally for confirmation and reconnection. This is not anonymous communication, and we do not use hardware fingerprinting to track a person.

Permissions and file selection

Local Network and Bluetooth permissions support nearby discovery and connections. The camera scans pairing QR codes; NFC handles temporary pairing invitations on supported devices. Denying permission makes the corresponding feature unavailable. You can change permissions in system Settings. You select files and photos through system pickers; the app does not read your system contacts. Selecting photos does not give us access to your entire library. Local temporary or staging copies may be created for drafts and transfers.

Local storage, deletion and backups

Contacts, conversations, drafts and transfer records are stored in a local database. Received file contents are not covered by database encryption. The optional startup password protects local data; the default unlocked mode is not independent personal-password protection.

Deleting local history does not remove peer or separately saved copies. Unpairing revokes the local relationship; it is not permanent blocking. Undeleted local records may remain indefinitely. System backups, manual backups and uninstall behavior vary by platform; uninstalling does not guarantee removal of keychain entries, backups or external copies. We cannot remotely read or erase records on another device.

Platform differences

Android: Bluetooth permissions support scanning, advertising and connections. On Android 11 and earlier, scanning may also require location permission or location services; these are not used to track your location. Notifications and a foreground service support connection status. APK updates require user-confirmed installation. System automatic backup is disabled (allowBackup=false), and Android Keystore protects silent-unlock material. Manufacturer migration tools or manual copies may still exist.

iOS/iPadOS and macOS: local-network, Bluetooth and feature permissions are requested as required by the system. Silent unlock uses the system Keychain; iOS uses device-only, non-synchronizing key entries. Some logs, reports and reconstructible temporary files are excluded from system backup; received files are not automatically excluded. macOS backups and file access also depend on the user account and system settings.

Windows: local records are stored in the user data directory. Deleting the portable program folder does not delete those records. Firewall and Bluetooth settings affect discovery and connections. Backup or synchronization tools may copy local files; retention depends on those tools and user settings.

Diagnostics and voluntary feedback

The app records runtime status and errors locally. Exporting diagnostics requires your action. It has no advertising or automatic telemetry-upload feature. Help and feedback opens your email app without automatically adding logs, conversations, files or full device identities, and does not send mail automatically. Include only information needed for troubleshooting, not passwords, private keys or private conversations. Apple handles diagnostics under its platform rules; diagnostics made available to us are used only for reliability improvements and support.

Support email and privacy requests

We and our email provider Gmail process the email address, message and attachments you voluntarily send only for support, safety feedback and handling requests, not advertising or sale. We retain support correspondence for at most 12 months after the issue is closed, except information needed for legal requirements or unresolved disputes. Email us to request access, correction or deletion of information we actually hold; we handle requests under applicable requirements. This does not include copies controlled by users on other devices.

Website and external services

skstu.com provides project, download, privacy and support information and does not host conversations or transferred files. It sets no cookies and loads no third-party analytics; language preferences are stored locally. Access logs contain IP address, time, host, path without query parameters, status, response size, duration, referring host, browser information and test markers for operations, security and aggregate analysis. They do not record authentication headers, cookies or request bodies.

Website logs rotate daily with 14 historical files retained. Security evidence is retained until an incident is resolved; older historical logs may contain query parameters or full referrer URLs. External links and Gmail, GitHub and Apple services are also subject to their providers’ privacy rules. Website hosting and email processing may take place outside your region.

Test distribution and policy changes

App Store and TestFlight installation does not require UDID registration with us. Separately arranged Ad Hoc testing registers devices with Apple for signing and targeted distribution. Withdrawal stops future targeted distribution and removes registration information we hold; Apple’s records and installed copies follow its rules. Zhiyu is a general-purpose device-transfer tool, not specifically directed to children. Changes to this policy will update this page and its effective date. Contact k34ubll5@gmail.com for privacy questions.