Companion Reader E-Book Reader
Home Product Download Membership
Privacy Policy Terms of Service API Key Safety Support Center Account Deletion FAQ
Privacy Policy

Privacy Policy

This policy explains how Companion Reader handles accounts, books, reading records, notes, AI Keys, membership and device data across web, mobile and desktop.

Last updated: July 13, 2026. We aim to explain data use and protection clearly.

1. Information We May Collect

Account & Login

Phone, email, credentials, registration time, membership status and device login records for account identification, security and service activation.

Books & Reading Data

Uploaded EPUBs, covers, titles, authors, categories, reading progress, settings and recent history.

Notes & Learning Content

Underlines, highlights, quotes, thoughts, chapter summaries, AI chats and exports for sync and cross-device display.

API Key & AI Settings

When users configure third-party AI Keys, we process them only to provide AI features, with encryption and masking to reduce leak risks.

Device & Log Data

App version, device type, OS version, error logs and network status for debugging crashes, sync failures and performance.

Payment & Order Data

Membership plans, order numbers, payment status, activation and expiry dates. Sensitive payment data is handled by payment providers.

2. How We Use Information

  • Provide core features: bookshelf, reader, notes, highlights, quotes, AI chat and cross-device sync.
  • Identify membership benefits, quotas, upload limits, AI toggles and export permissions.
  • Optimize cover loading, book open speed, error messages and cross-device experience.
  • Handle feedback, support, troubleshooting and security risk management.
  • With consent, show product updates, download links and membership promotions.

3. User-Uploaded Books & Notes

Uploaded books and notes are user content. We don't use them for public display, sale, model training or sharing with unrelated parties. Storage and processing is limited to what's needed for sync, parsing, cover generation, AI reading and backup.

Users must confirm lawful ownership and usage rights. Don't upload content that infringes copyright, privacy, trade secrets or other rights.

4. AI Features & Third-Party Services

When using AI chat, summaries, extraction, categorization or correction, relevant text, notes or input may be sent to the chosen AI provider. If using your own Key, cost, quota and model rules are set by that provider.

The product clearly labels "User API" vs "System API" to help users understand cost and quota sources.

5. Information Sharing & Entrusted Processing

We may use cloud servers, object storage, databases, payment, SMS/email, AI providers and crash analysis tools as needed. Partners are required to process data only for agreed purposes with appropriate security.

We don't sell personal information except as required by law, authorized by users, or necessary for service.

6. Retention & Deletion

We retain data needed for service while the account exists. After deleting books, notes, Keys or the account, we remove or anonymize data within a reasonable period, except where law or dispute resolution requires otherwise.

7. User Rights

  • Access, copy, correct and supplement personal information.
  • Delete books, notes, API Keys, reading records or account.
  • Withdraw non-essential consent, e.g. marketing notifications.
  • Delete account and request cessation of non-essential data processing.
  • Report privacy concerns or complaints via support channels.

8. Security Measures

We use HTTPS, access control, key masking, log sanitization, backups and permission isolation. No system is perfectly secure — users should also protect passwords, API Keys and device access.

9. Contact Us

For privacy, data deletion or account questions, contact us via in-app feedback or official channels on the website.

Companion Reader AI-Enhanced Deep Reading Tool
Privacy Policy Terms of Service Membership API Key Safety Support Center Account Deletion FAQ