Privacy Policy for Qalculyn

Qalculyn (“the app”) is an offline mathematical computing system and calculator engineered and published by Spring Web Solutions (“we”, “us”, or “our”). We believe user privacy is a fundamental right. This Privacy Policy details our architecture, principles, and full compliance with the Google Play Developer Content Policy and international privacy standards.

1. Zero Personal Data Collection

Qalculyn does not collect, harvest, log, or transmit any Personally Identifiable Information (PII). We do not require account registration, passwords, emails, contact lists, physical addresses, or phone numbers to use any part of the application.

2. Physical 100% Offline Architecture

The application is engineered exclusively for local on-device execution:

• No Internet Permission: The Android permission android.permission.INTERNET is completely omitted from the application's AndroidManifest.xml. The Android OS physically prevents the app from opening network sockets.
• Local Processing: All scientific computations, equation solvers, calculus algorithms, geometry canvas computations, and step explanations run entirely on your device's local CPU.
• No Telemetry or Remote Crash Reports: We do not embed remote diagnostic reporters, performance monitors, or telemetry SDKs.

3. Local Storage & User Notes

Any data created by you during calculation workflows is stored strictly within Android app-scoped internal storage:

• Calculation History & Custom Study Notes: Persisted in a local, unshared SQLite database stored within the app's sandboxed data partition.
• User Preferences: Dark mode preference, AMOLED mode toggle, and chosen theme accent colors are saved locally via Android SharedPreferences.
• Data Deletion: You have full control. You can wipe your calculation history at any time using the “Clear All” option inside the History sheet, or by tapping “Clear Storage” in Android System Settings.

4. Zero Third-Party Advertising & Tracking

Qalculyn is entirely ad-free:

• We do not embed Google AdMob, Unity Ads, Meta Audience Network, or any other ad broker SDKs.
• We do not integrate Google Analytics for Firebase, Facebook Pixel, Mixpanel, or third-party behavioral trackers.
• Your math expressions, problem notes, and usage behavior are never monetized, sold, or shared with third parties.

5. Android Device Permissions Audit

Qalculyn adheres to the principle of least privilege and requests zero dangerous permissions:

• No Camera or Video Recording access
• No Microphone or Audio Recording access
• No GPS or Network Location access
• No Contacts or Calendar access
• No External Storage / Media Library access
• No Background Service or Auto-start on boot access

6. Children's Online Privacy & Family Policies

Because Qalculyn collects zero personal information, transmits no network packets, and contains no advertisements or user-generated communications, it fully conforms with:

• The United States Children's Online Privacy Protection Act (COPPA).
• The European Union General Data Protection Regulation (GDPR / GDPR-K).
• The Google Play Families Policy requirements.

7. Google Play Data Safety Declaration Summary

When reviewing Qalculyn on the Google Play Store, our Data Safety declaration is transparent and verifiable:

• Data Collected: No data collected.
• Data Shared: No data shared with third parties.
• Security Practices: Data is not transmitted because there is no network connection.

8. Contact & Publisher Information

If you have questions, feedback, or inquiries regarding this Privacy Policy or the security of Qalculyn, please reach out to: