Privacy Policy

Last updated: January 19, 2026

1. Introduction

Tathastu ("we," "us," or "our") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our secure digital messaging service.

Tathastu is a service that allows you to create encrypted messages for delivery to your designated nominees after Life Status Verification. We take your privacy seriously, especially given the sensitive nature of the messages you entrust to us.

2. Information We Collect

2.1 Information You Provide

  • Account Information: When you sign up using Google Sign-In, we receive your email address, name, and Google account identifier.
  • Profile Information: Phone number (optional) for account recovery and verification purposes.
  • Nominee Information: Names, email addresses, phone numbers, and relationships of people you designate to receive your messages.
  • Encrypted Messages: The content of your messages, which is encrypted client-side before transmission. We store only the encrypted data.
  • Passphrase Salt: A cryptographic salt used for key derivation. Your actual passphrase is never transmitted or stored on our servers (unless you opt into escrow recovery).

2.2 Information Collected Automatically

  • Login Activity: We track your last login date to monitor account activity as part of our service (45-day and 55-day inactivity thresholds).
  • Device Information: Browser type, operating system, and device identifiers for security and troubleshooting.
  • Usage Data: Pages visited, features used, and interaction patterns to improve our service.

2.3 Optional Escrow Information

If you opt into our passphrase escrow recovery service, your passphrase is encrypted using threshold encryption (requiring two separate keys to decrypt) and stored in our secure vault. This is entirely optional and requires your explicit consent.

3. How We Use Your Information

  • To provide and maintain our encrypted messaging service
  • To authenticate your identity and secure your account
  • To deliver messages to your nominees after Life Status Verification
  • To monitor account activity for service continuity
  • To send you service-related notifications (login reminders, important updates)
  • To respond to your inquiries and provide customer support
  • To comply with legal obligations
  • To improve and develop our service

4. Encryption & Data Security

4.1 Client-Side Encryption

Your messages are encrypted on your device using AES-GCM-256 encryption before being transmitted to our servers. We use PBKDF2 with 100,000 iterations for key derivation. This means:

  • We cannot read your message contents
  • Your passphrase never leaves your device (unless escrow is enabled)
  • Only someone with your passphrase can decrypt your messages

4.2 Threshold Encryption (Escrow)

If you enable escrow recovery, your passphrase is encrypted with two layers of encryption requiring both our Founder key and Operator key to decrypt. No single person can access your escrowed passphrase.

4.3 Security Measures

  • All data transmitted over HTTPS/TLS
  • Database encryption at rest
  • Row-level security for data access control
  • Regular security audits and monitoring
  • Comprehensive audit logging of all sensitive operations

5. Data Sharing & Disclosure

5.1 We Share Information With:

  • Service Providers: Firebase (authentication), Hasura (database), Vercel (hosting), and email/SMS providers for notifications.
  • Your Nominees: After Life Status Verification, we share your decrypted messages with your designated nominees.
  • Legal Authorities: When required by law, court order, or to protect our rights and safety.

5.2 We Do Not:

  • Sell your personal information to third parties
  • Share your encrypted message contents with anyone without the passphrase
  • Use your data for advertising purposes

6. Life Status Verification & Message Delivery

When we receive indication of your passing (through inactivity monitoring or direct notification), our administrator will:

  1. Verify the life status through legal documentation or established processes
  2. Obtain your passphrase (from your will/legal documents or escrow if enabled)
  3. Decrypt your messages using the passphrase
  4. Contact your nominees and provide secure access to their assigned messages

All of these actions are logged in our audit system for transparency and accountability.

7. Data Retention

  • Account Data: Retained as long as your account is active, plus 90 days after deletion request.
  • Encrypted Messages: Retained until delivered to nominees or account deletion.
  • Audit Logs: Retained indefinitely for compliance and security purposes.
  • Nominee Access Tokens: Expire after 7 days, records retained for 30 days after access.

8. Your Rights

Depending on your location, you may have the right to:

  • Access: Request a copy of your personal data
  • Correction: Update inaccurate information
  • Deletion: Request deletion of your account and data (note: this permanently destroys your encrypted messages)
  • Portability: Export your data in a machine-readable format
  • Objection: Object to certain processing activities
  • Withdraw Consent: Disable escrow recovery at any time

To exercise these rights, contact us at privacy@tathastu.app.

9. International Data Transfers

Your data may be processed in countries outside your country of residence. We use appropriate safeguards including standard contractual clauses where required. Our service providers maintain compliance with applicable data protection regulations.

10. Children's Privacy

Tathastu is not intended for users under 18 years of age. We do not knowingly collect personal information from children. If you believe we have collected information from a minor, please contact us immediately.

11. Cookies & Tracking

We use essential cookies for authentication and session management. We may use analytics cookies to understand how you use our service. You can disable non-essential cookies through your browser settings.

12. Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of material changes via email or prominent notice on our service. Your continued use after changes constitutes acceptance of the updated policy.

13. Contact Us

For privacy-related inquiries: