Hamster PhotoBackupHamster PhotoBackup Privacy Policy
Effective date: October 29, 2026
Operator: Shanghai Xiangsu Hangji Technology Co., Ltd. (上海像素航迹科技有限公司, "we" or "us")
Hamster PhotoBackup (仓鼠相册, "the Software") consists of a phone app (iPhone and Android) and a computer app (Mac and Windows). This policy explains what information the Software handles, why, where it is stored, and how you can manage it. If this English version differs from the Chinese version, the Chinese version prevails.
In short: your photos travel only between your own phone and your own computer, over your home network. We run no servers of our own, require no account, and do not collect your photos or any personal information for analytics or advertising. The only thing that leaves your devices is an anonymous crash report when the app hits an error, which you can turn off in Settings.
1. Information we do not collect
The Software has no cloud service and no account system. We do not collect, upload or store your photos, videos, photo locations, album names, device names or usage history. The Software contains no advertising, analytics or user-tracking tools, and we never sell or share your information with any third party. Crash reports are described in section 5.
2. Information processed on your devices
To back up and browse your photos, the Software processes the following information on your phone and computer. All of this happens on your devices or between your paired phone and computer, never through us.
| Information | Purpose | Where it is stored |
|---|---|---|
| Photos, videos and their original files | Back up to the computer as-is; show them on a timeline on the phone; save them back to the phone | Your phone's photo library; the library folder you chose on your computer |
| Photo metadata (capture date, location, dimensions, albums, whether it is a Live Photo, etc.) | Preserve capture information; organize by date and album; create folders that match your albums | Inside the photo files; the library database on your computer; local cache on your phone |
| Thumbnails | Fast browsing on the phone and computer | A thumbnail folder inside the library; local cache on your phone (can be cleared and rebuilt at any time) |
| Device model and device name | Let the two devices recognize each other when pairing; name each phone's folder on the computer after its model | Your paired phone and computer |
| Pairing information (computer name, local network address, certificate fingerprint, access token) | Reconnect automatically and securely on the same network | The phone's system secure storage (Keychain on iPhone, Keystore-encrypted storage on Android); the computer app's database |
| Backup records (which photos are backed up, today's used quota) | Avoid duplicate transfers, resume interrupted transfers, and tell which photos are safe to delete | On the phone; the library database on your computer |
| Diagnostic logs (app status and errors) | Help troubleshoot problems when you choose to export and send them to us | On the phone and computer, about 2 MiB per file, two files kept |
Diagnostic logs never contain photo content, access tokens, keys or pairing codes. Logs stay on your devices. We only see a log if you double-tap the version number at the bottom of Settings to export it and then send it to us yourself. We use it only to investigate the problem you reported and delete it once the problem is resolved.
3. System permissions
The Software asks for the following permissions only when you use the related feature. You can decline, or turn them off at any time in your phone's system settings; doing so only affects that feature.
| Permission | Purpose | If declined |
|---|---|---|
| Photos and videos (read) | Read original photo and video files to back them up to your paired computer; show and organize photos on the phone; delete backed-up photos after you confirm | Cannot back up, browse or organize photos on the phone |
| Photo locations (Android) | Read the location recorded in each photo so it is backed up with the original | Cannot back up photos; the app tells you instead of backing up copies with the location removed |
| Photos (add only, iPhone); Storage (Android 9 only) | Save photos from the computer back to your phone's photo library | Cannot save photos back to the phone |
| Local Network (iPhone) | Find and connect to your computer on your home network; Android needs no separate permission | Cannot connect to the computer |
| Camera | Scan the pairing QR code shown on the computer; the camera image is never saved or uploaded | Cannot pair by QR code; you can still pair by picking the computer from the list |
The computer app asks for access to the library folder you choose and any watched folders you add, and keeps the computer awake only while a transfer is in progress. On Windows, the installer adds a firewall rule so your phone can reach the computer on your local network, and removes it when you uninstall.
4. Transmission and security
The phone and computer communicate only within private local network address ranges, always over an encrypted connection. The phone trusts only the certificate of the computer it paired with and never falls back to any other certificate. Pairing requires matching the same 6-digit number on both devices and approving on the computer, or using a one-time QR code on the computer that is valid for 5 minutes.
Every transferred file is verified with SHA-256 and only counts as backed up once it matches the original on the phone.
Your backup lives on your own computer or drive, so its security depends on that computer or drive. We recommend setting a login password on the computer, turning on disk encryption (for example FileVault on macOS or BitLocker on Windows), and keeping external drives in a safe place.
5. Third-party services
Apart from the crash reports below, the Software does not include any third-party SDK that sends data off your devices. The following are handled by the operating system, Apple or Sentry and are covered by their own privacy policies:
iCloud Photos (iPhone). If you use iCloud Photos and agree to back up photos stored only in iCloud, iOS downloads the original files from iCloud to your phone, and the Software then sends them to your computer. The download is performed by Apple.
App Store purchases (iPhone). When you buy the unlimited upgrade, payment is handled by Apple and your purchase status is verified locally on your phone. We cannot access your Apple Account or payment information.
Crash reports (Sentry). To find and fix problems, when the app crashes or hits an unhandled error it sends an error report to Sentry, an error-monitoring service provided by Functional Software, Inc. A report contains the error type and message, the program call stack where it happened, the app version, and the device model, system version, language and similar runtime details. Before sending, the app removes file paths and file names, local network addresses, access tokens, pairing codes and certificate fingerprints on your device. Reports never include photos, videos, album names, device names or account information, are not linked to your identity, and are not used for advertising or tracking. We do not turn on performance monitoring, usage statistics, screenshots or screen recording. Reports are used only to find and fix problems and are deleted automatically after no more than 90 days at Sentry. Sentry's servers are located outside mainland China and are covered by the Sentry Privacy Policy. You can turn off "Send crash reports" in Settings on the phone or computer at any time; sending stops immediately, and crashes and errors are then only kept in the log on your device.
6. Your choices
Because your information stays on your own devices, you can manage it directly:
- View or turn off the Software's permissions in your phone's system settings.
- Unpair a phone on the Devices page of the computer app, or unpair the computer in the phone app.
- Deleting the phone app removes the pairing information, cache, backup records and logs on the phone; photos in your phone's photo library are not affected.
- Deleting the library folder on your computer removes all backups and the library database. Do this only when you no longer need those photos.
Since we do not hold your personal information, we cannot and do not need to look it up, correct or delete it for you. Crash reports contain nothing that identifies you, so we cannot match a report to a person; to stop sending them, turn off "Send crash reports" in Settings on the phone or computer. If you have any questions about this, please contact us.
7. Children
The Software is intended for general family use. Children under 14 should use it with the consent and guidance of a parent or guardian. We do not knowingly collect any personal information from children.
8. Changes to this policy
When the Software's features or the way it handles information change, we will update this policy and publish it on this page and in the app. If a change involves collecting new personal information or sending information off your devices, we will notify you clearly before it takes effect and ask for your consent again.
9. Contact us
If you have any questions, comments or complaints about this policy, contact us and we will reply within 15 business days.
Email: [email protected]