Privacy Policy

2. Who We Are

Sino Privacy Vault is an app for Android and Windows, published by apps by ibi, that encrypts, backs up and restores your files using your own cloud storage accounts.

• Sino is not a cloud storage provider.
• We run no servers that store your files, your keys or an account for you. The only online services we run are this website and its search (see Section 15).

3. What the Apps Handle on Your Device

The apps process the following on your device. None of it is sent to us.

• Your files: the files and folders you choose to back up or move into the Local Vault.
• Cloud sign-in details: the email address of your Google or MEGA account, the access tokens or session that keep you signed in, and the access keys of any S3 storage you add. They are stored encrypted on your device.
• Your device's name: your phone's make and model, or your Windows computer name, stored encrypted in your vault's device list (see Section 5).
• Legacy Handover: if you use it, the names you give your beneficiaries and the public keys of their devices.
• Your settings, and an encrypted list of your files and folders.

Device Permissions

On Android, Sino asks for access to the photos, videos, audio and folders you choose to protect, for notifications (to show backup progress), and for the camera and NFC only to pair with a beneficiary's device. Fingerprint and face unlock are handled by Android or Windows: Sino never receives your biometric data.

Sino does not request access to your contacts, calendar, messages, call history or location.

4. Information We Do Not Collect

We do not receive, collect or store:

• Your files or their contents
• File and folder names
• Your master password
• Your 24-word recovery phrase
• Your encryption keys
• Your cloud passwords or tokens
• Biometric information
• Your location
• Your contacts
• Advertising identifiers
• Usage analytics from the apps
• Payment card details (payments are handled by Google Play, the Microsoft Store or our payment provider)

5. What Is Stored in Your Cloud

Everything Sino uploads goes to the cloud accounts you connect. It is encrypted on your device first:

• Your files, each encrypted with its own key (AES-256-GCM), under scrambled names.
• Encrypted lists of your files and folders, an encrypted snapshot of your vault, and an encrypted backup of your settings.
• An encrypted backup of your vault key that only your 24-word recovery phrase can open, and a random public value used to check that phrase, which reveals nothing.
• If you add a recovery passkey, a copy of your recovery phrase encrypted with that passkey.
• If you use Legacy Handover, the handover sealed so that only your beneficiaries' devices can open it.
• Your vault's signed device list. Each device's name and type (for example a phone model, or your Windows computer name) are encrypted; the list shows unencrypted only a random id for each device, its public keys and when it joined. It holds no copy of your vault key.

Your cloud provider can therefore see that you use Sino, roughly how much you store and how large your files are, when you upload, and how many devices your vault has. It cannot see your files' contents, their names or your folder names, the names of your devices, or any key that opens them.

Your use of a cloud provider is governed by its own privacy policy and terms.

6. Encryption Keys and Recovery

Your vault's keys are created on your device. On each device, the vault key is protected by your master password (stretched with Argon2id) and, if you turn it on, by a fingerprint, face or Windows Hello key held in the device's security chip (Android Keystore, StrongBox or TEE, or the Windows TPM, with Windows DPAPI where there is no TPM).

• Your keys are never sent to us.
• Your keys are uploaded to your cloud only in encrypted form, as described in Section 5.
• Your master password is never uploaded and works only on the device where you set it.

You can recover your vault on a new device with your 24-word recovery phrase, or with a recovery passkey if you set one up. A passkey is stored by your passkey provider (for example Google Password Manager, Windows Hello, or a security key) under that provider's own policy.

We have no copy of your keys and no way to recover your vault. If you lose your recovery phrase, your recovery passkey and every device that can unlock your vault, your encrypted data cannot be recovered by anyone.

7. Storage on Your Device

• Sino's database is encrypted (SQLCipher), and its most sensitive fields are encrypted again.
• Local Vault files are stored encrypted in Sino's private storage, out of reach of other apps. Files kept only on a device are lost if the device is lost or reset, or (on Android) if Sino is uninstalled.
• Files restored in Secure mode stay encrypted in Sino's private storage. They are deleted by an emergency wipe (the Terminus Protocol) or when you clear them in Settings. Files restored in normal mode are ordinary files that other apps can see.
• A small encrypted cache of your dashboard (statistics and recent file names), sealed with your vault's key, so Sino opens quickly.
• The decoy vault, if you create one, is stored on that device only.

The Terminus Protocol (the emergency wipe) erases Sino's keys and data from the device. It does not delete your cloud backups; deleting those is the separate Wipe Cloud action.

8. Virtual Drive

While your vault is unlocked, Sino can show it in the Android Files app or as a Windows drive (using Dokany), so other apps can open your files.

• Files are decrypted in memory as apps read them.
• In Local Vault folders, apps can also save files; what they write is held encrypted until it is saved into your vault.
• An app you open a file with may keep its own copy, such as a thumbnail or a recent-files entry, under that app's own privacy practices.

9. Optional Features That Affect Privacy

• Metadata scrubbing (on by default): removes location and camera details from photos and videos before they are encrypted and uploaded.
• Video compression (off by default): re-encodes videos on your device to save space before they are encrypted.
• Device revocation checks: each device regularly reads your device list from your cloud, and again right after a wrong password is entered on it, so that a lost device you revoke can wipe itself.
• Wrong-password alerts (off unless you turn them on): if you switch them on for a device, then after wrong passwords are entered on it, it writes a small encrypted file to your cloud saying how many and when, and whether the right password followed (never what was typed). Only your other devices can read it; your cloud provider sees only that the file changed, and when.
• Legacy Handover: pairing with a beneficiary exchanges public keys by QR code, NFC or link, on your devices and theirs.

10. Google Drive

If you connect Google Drive, Sino requests one of the following permissions, depending on the storage mode you choose:

On Android, Google Drive sign-in goes through Google Play services. Sino cannot see your other Drive files, Gmail, Contacts, Calendar or Photos, and does not use your Google account for advertising, analytics, marketing or profiling.

Sino's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

11. MEGA and S3 Storage

Sino signs in to MEGA directly from your device using MEGA's own login, and keeps a MEGA session on your device rather than your password. For S3-compatible storage (such as Amazon S3, Cloudflare R2 or Backblaze B2), Sino stores the access keys you enter encrypted on your device and signs each request with them (AWS Signature Version 4).

12. Diagnostic Logs

Sino keeps diagnostic logs on your device to help fix problems. They are designed to exclude encryption keys, passwords, recovery phrases, authentication tokens, file contents, and file and folder names. Logs stay on your device unless you choose to export and send them to us.

13. Analytics and Advertising

• The Sino apps contain no analytics, crash-reporting or advertising code.
• We do not build advertising profiles or sell personal information.
• Our website counts visits without cookies (section 15).

Google Play and the Microsoft Store give us aggregated statistics about installs, crashes and ratings, under their own privacy policies.

14. Purchases

Sino for Windows is free for personal use. Sino for Android is bought through Google Play, which handles payment. We never receive your card or billing details.

Businesses pay for Sino by subscription. The payment provider named at checkout handles the payment and your card details. We receive what we need to issue and manage the business license, such as the organisation's name, a billing contact's email address, the subscription tier and the number of people it covers.

The app may check a business license on your device. That check does not send your files, file names or keys to us.

15. Our Website

Our website, sinosecure.app, is hosted by Cloudflare, which processes standard request information such as your IP address to deliver and protect the site.

• Search and chat: what you type in the site search or the chat assistant is sent to our search service (ai.sinosecure.app, run on Cloudflare) to find answers. Answers from the chat assistant are written by AI and can be wrong. Please do not enter personal information there.
• Beta sign-up: if you join the beta waitlist, the form (provided by Tally) collects the details you enter, such as your email address. We use them only to contact you about Sino's beta and releases.
• Visit statistics: Cloudflare Web Analytics counts visits to the website: the page, the page or site you came from, and your browser, device type and country. It uses no cookies or local storage and does not identify you or follow you across sites.
• Icons: pages load their icon script from jsDelivr, which receives your IP address when it serves it. Fonts are served from our own site.
• Email: if you email us, we use your message and address only to reply.

We do not use advertising or cross-site tracking cookies.

16. Children's Privacy

Sino is not directed at children under the age required by applicable law, and we do not knowingly collect personal information from children.

17. Data Retention

• Your encrypted cloud data stays in your cloud accounts until you delete it, for example with Wipe Cloud. Uninstalling Sino or an emergency wipe does not remove it.
• Data on your device stays until you delete it, wipe it, or (on Android) uninstall Sino.
• Beta sign-up details are kept until the beta ends or you ask us to delete them; support emails are kept only as long as needed to help you.

18. Your Rights

Depending on where you live, you may have rights to access, correct, delete, restrict or move your personal information.

Because your files and keys stay with you, you exercise these rights over them directly, in the app and in your cloud accounts. For the little information we do hold (beta sign-ups and emails you send us), contact us at support@sinosecure.app and we will help.

19. Security

Sino uses modern, standard cryptography and is designed so that your sensitive information stays under your control. No software can guarantee absolute security: see what Sino cannot protect you from and its audit status.

20. Third-Party Services

Depending on the features you use, Sino and its website work with these services, each under its own privacy policy and terms:

• Google Drive (and Google Play services, for sign-in on Android), MEGA, and S3-compatible storage providers
• Android Keystore, Windows TPM, Windows Hello and passkey providers such as Google Password Manager
• Google Play and the Microsoft Store, for downloads, purchases and updates, and the payment provider named at checkout, for business subscriptions
• Cloudflare (website hosting, search and visit statistics), Tally (beta sign-up), jsDelivr (website icons)

21. Microsoft Store

If you obtain Sino through the Microsoft Store, Sino's Terms of Service are a binding agreement between you and apps by ibi. Microsoft is not responsible for the app or its content. Your use of the app through the Microsoft Store is also subject to Microsoft's Standard Application License Terms unless otherwise specified.

22. International Data Transfers

Your cloud provider may store your encrypted data in data centres in other countries. Because it is encrypted before it leaves your device, providers store only encrypted content, apart from the device-list details described in Section 5. Our website providers may also process website data in other countries.

23. Changes to This Privacy Policy

We may update this Privacy Policy. The "Last Updated" date at the top shows the latest version, and the apps ask you to review important changes.

24. Contact

If you have questions about this Privacy Policy or Sino's privacy practices, contact us at:

25. Privacy Principles

• Your files belong to you.
• Encryption happens before upload.
• Your cloud provider is treated as untrusted storage.
• Your encryption keys stay under your control.
• We collect only what we need, and nothing from inside the apps.
• We cannot read your files.