🔒 Privacy Policy

1. Who We Are

CantoneseEcho ("we", "us", "our") is an independent research and development project providing AI-powered Cantonese language tools including text-to-speech (TTS), speech-to-text (STT), and subtitle synchronization services. The platform is operated by an individual developer based in Canada and is not a registered corporation or commercial entity.

Our services are available globally at cantoneseecho.com and associated subdomains.

2. Information We Collect

2.1 Information you provide directly

• Account registration: Email address, username, and password (hashed — we never store plain-text passwords)
• Google OAuth sign-in: If you sign in with Google, we receive your Google account email address, display name, and Google user ID
• Waitlist sign-ups: Email address and optionally company name
• Contact form submissions: Name, email address, and message content
• Text input for TTS: The text you submit for speech synthesis
• Audio uploads for STT: Audio or video files you upload for transcription

2.2 Information collected automatically

• Usage logs: Which features you use, word counts processed, provider used (Edge TTS, Azure, Groq), and processing timestamps
• Session data: An anonymous session identifier for users who are not signed in, derived from IP address and browser information using a one-way hash (we cannot reverse this to identify you)
• IP address: Collected for session management and fraud prevention
• Browser information: Browser type and version, used for session hashing only

2.3 Information we do NOT collect

• Payment card details (handled entirely by Stripe or PayPal when active)
• Precise geolocation
• Device identifiers or advertising IDs
• Social media profile data beyond what Google OAuth provides

3. How We Use Your Information

• To provide the service: Processing your text through TTS, transcribing your audio through STT, and synchronizing subtitles
• To manage your account: Authentication, session management, and usage limit enforcement
• To improve the service: Aggregated, anonymized usage statistics help us understand which features are used most and where issues occur
• To communicate with you: Responding to contact form submissions and sending waitlist notifications you requested
• To prevent abuse: Enforcing daily usage limits and detecting fraudulent or abusive behaviour
• To comply with law: Meeting obligations under Canadian privacy legislation (PIPEDA) and other applicable laws

We do not use your personal information for advertising, profiling, or sale to third parties.

4. Third-Party Services

CantoneseEcho uses the following third-party services to operate. Each has its own privacy policy:

When you submit text to our TTS service or audio to our STT service, that content is transmitted to the relevant third-party processor (Microsoft or Groq) to generate the output. We do not control how these processors handle data beyond our API calls. Please review their privacy policies for details.

5. Data Storage and Retention

5.1 Database (SQLite)

We store the following in our database:

• User accounts (email, hashed password, username, tier, creation date)
• Usage logs (word count, feature used, provider, timestamp — not full text content beyond 500 characters for debugging)
• Waitlist email addresses
• Session identifiers for anonymous users

Account data is retained until you request deletion. Usage logs are retained for up to 12 months for service improvement purposes.

5.2 Audio files

Audio files generated by TTS are stored temporarily on our server and automatically deleted after 1 hour. Audio files uploaded for STT are deleted immediately after transcription is complete.

5.3 Transcript files

Transcript and SRT output files from STT or subtitle sync are stored temporarily and automatically deleted after 24 hours.

5.4 Location of data

### 5.4 Location of data CantoneseEcho is hosted on Fly.io infrastructure in the Toronto, Canada region (yyz). Our third-party processors (Microsoft Azure, Groq, Google Gemini) may process data on servers located in the United States or other countries where they operate; please review their respective privacy policies (linked in Section 4) for details on their data center locations.

6. Cookies and Sessions

We use a single session cookie to maintain your login state. This cookie is:

• HTTP-only (cannot be read by JavaScript — protects against XSS attacks)
• SameSite=Lax (protects against CSRF attacks)
• Not used for advertising or tracking across other websites
• Deleted when you sign out

We do not use third-party advertising cookies. We do not use Google Analytics or similar tracking services at this time.

Your language preference (EN/繁中) is stored in your browser's localStorage — this remains on your device and is not transmitted to our servers.

7. Google OAuth Sign-In

If you choose to sign in with Google, we receive the following information from Google:

• Your Google account email address
• Your Google display name
• Your Google user ID (a unique number — not your Google password)

We use this information only to create and manage your CantoneseEcho account. We do not access your Google Drive, Gmail, contacts, or any other Google services.

You can revoke CantoneseEcho's access to your Google account at any time via your Google Account permissions page. Revoking access does not delete your CantoneseEcho account — contact us to request account deletion.

8. Audio and Transcript Data

When you use our Speech-to-Text (STT) feature:

• Your uploaded audio file is sent to Groq (Whisper model) or Microsoft Azure for transcription
• The audio file is deleted from our servers immediately after transcription completes
• The transcript output is stored temporarily (up to 24 hours) so you can download it
• We do not permanently store the content of your audio recordings

When you use our Text-to-Speech (TTS) feature:

• Your input text is sent to Microsoft Edge TTS or Azure Speech for synthesis
• We store up to 500 characters of your input text in usage logs for debugging purposes
• Generated audio files are deleted after 1 hour

Please do not submit audio recordings or text containing sensitive personal information (e.g. medical information, financial details, passwords). Our service is designed for language processing, not secure document handling.

9. Sharing and Disclosure

We do not sell, rent, or trade your personal information. We may share information in the following limited circumstances:

• Service providers: Third-party processors listed in Section 4 receive only the minimum data needed to perform their function
• Legal requirements: We may disclose information if required by law, court order, or to protect the rights, property, or safety of our users or others
• Business transfer: If the project is transferred or acquired, user data may transfer as part of that transaction. We will notify users via email or prominent notice on the site

10. Your Rights

Depending on your location, you may have the following rights regarding your personal information:

• Access: Request a copy of the personal information we hold about you
• Correction: Request correction of inaccurate or incomplete information
• Deletion: Request deletion of your account and associated personal data
• Withdrawal of consent: Withdraw consent for processing where consent is the legal basis
• Data portability: Request your data in a machine-readable format
• Opt-out of communications: Unsubscribe from any emails we send

To exercise any of these rights, please contact us via the Contact page. We will respond within 30 days. Some requests may be subject to legal limitations.

11. Children's Privacy

CantoneseEcho is not directed to children under the age of 13. We do not knowingly collect personal information from children under 13 without verifiable parental consent. If you believe a child under 13 has provided us with personal information, please contact us immediately and we will delete it.

Users between 13 and 18 should use the service only with parental awareness and consent.

12. Security

We implement reasonable security measures to protect your personal information, including:

• Passwords are hashed using industry-standard algorithms (Werkzeug/bcrypt) — we never store plain-text passwords
• Session cookies are HTTP-only and SameSite=Lax to prevent common web attacks
• HTTPS encryption for all data in transit
• Webhook endpoints are verified using HMAC signatures
• Database access is restricted to the application server

No system is completely secure. We cannot guarantee absolute security of your information. If you believe your account has been compromised, please contact us immediately.

13. Canadian Privacy Laws (PIPEDA)

As a Canadian-operated service, we comply with the Personal Information Protection and Electronic Documents Act (PIPEDA). Under PIPEDA, you have the right to:

• Know why we collect, use, and disclose your personal information
• Expect us to collect only the information necessary for identified purposes
• Know that your information will be protected by appropriate safeguards
• Access your personal information and challenge its accuracy
• Complain to the Office of the Privacy Commissioner of Canada if you believe your privacy rights have been violated

For CASL (Canada's Anti-Spam Legislation) compliance: we only send emails you have explicitly requested (waitlist sign-ups, account notifications). We do not send unsolicited commercial electronic messages.

14. International Users

CantoneseEcho is operated from Canada and primarily serves users in Canada, the United States, and other countries with significant Cantonese-speaking populations (UK, Australia, Hong Kong SAR).

If you are located in the European Union or European Economic Area, your data is processed under our legitimate interests to provide the requested service. You may have additional rights under GDPR — please contact us to exercise them.

By using our service, you consent to the transfer of your information to Canada and to third-party processors in the United States (Groq, Microsoft Azure, Google Germini) for processing.

15. Changes to This Policy

We may update this Privacy Policy from time to time. When we make material changes, we will:

• Update the "Last updated" date at the top of this page
• Post a notice on the home page for 30 days
• Send an email notification to registered users if the changes are significant

Continued use of the service after changes are posted constitutes acceptance of the updated policy.

16. Contact Us

If you have questions, concerns, or requests regarding this Privacy Policy or your personal data, please contact us through our Contact page.

We will respond to all privacy-related inquiries within 30 days.