Privacy Policy

Effective Date: September 8, 2026

Welcome to Calculator Lock. We are committed to protecting your privacy and ensuring that your personal data is handled securely and transparently. This policy explains our data practices for the Calculator Lock mobile application.

1. Local-First Data Architecture

Calculator Lock is built on a strict "Local-First" privacy model. We do not operate any cloud servers to store your private files.

Vault Content: Your photos, videos, and documents are encrypted locally on your device using hardware-backed AES-256-GCM encryption. We have no technical access to your encrypted data.

2. Data Collection & Processing

  • Personal Identifiable Information: We do not require account registration. We do not collect your name, email address, or phone number.
  • Usage Data: We may process non-sensitive metadata to improve app performance, such as crash reports and system maintenance status.

3. Third-Party Integrations

To provide high-quality services and monetization, we integrate trusted third-party providers:

  • Google AdMob Used for advertising. They may collect device identifiers to serve relevant ads.
  • OneSignal Used for push notifications and security alerts. They process device metadata to facilitate delivery.

4. Security Standards

Your security is our top priority. We implement the following protections:

  • Android Keystore: Encryption keys are stored in a hardware-isolated environment.
  • PBKDF2 Hashing: Your PIN and security answers are protected using salted, high-iteration cryptographic hashing.
  • FLAG_SECURE: Prevents vault content from appearing in screenshots or recent app previews.

5. System Permissions

The app requests only essential permissions:

  • Internet: To load advertisements and verify security status.
  • Notifications: To deliver important security updates.
  • Vibration: To provide haptic feedback during use.

6. Children's Privacy

The App is not intended for use by children under the age of 13. We do not knowingly collect any information from children.

7. Contact & Support

If you have questions regarding this Privacy Policy or the app's functionality, please reach out to us using the contact details provided in our official Google Play Store listing.