1. Introduction
CALQENTRA ("CALQENTRA", "we", "us", or "our") is an engineering calculator and reference application designed to provide engineering calculations, technical reference information, project functionality, and related tools.
This Privacy Policy explains how information may be collected, used, stored, and processed when you use the CALQENTRA application.
By using CALQENTRA, you acknowledge the practices described in this Privacy Policy.
2. Information We May Collect
Account Information
If you create a CALQENTRA account, we may process information required to create and maintain your account, such as your email address, authentication identifiers, and information associated with your account.
Google Sign-In
If you choose to sign in using Google, authentication information provided through Google's authentication services may be processed to authenticate your account.
Calculator and Project Information
Depending on the features you use, CALQENTRA may store information associated with your calculator usage, saved projects, calculation history, favorites, and related application settings.
Purchase and Subscription Information
CALQENTRA may process information necessary to determine entitlement to paid or Pro features purchased through Google Play.
Payment transactions are processed by Google Play. CALQENTRA does not directly collect or store your complete payment-card information.
Analytics and Diagnostic Information
CALQENTRA may use analytics and crash-reporting services to understand application usage, diagnose technical problems, improve reliability, and improve the application.
Advertising Information
The free version of CALQENTRA may display advertisements. Advertising services such as Google AdMob may process device or advertising information in accordance with their own privacy policies and applicable laws.
3. How We Use Information
Information may be used to:
- create and maintain user accounts;
- authenticate users;
- provide calculator and engineering-reference functionality;
- save and synchronize user projects and related information;
- provide saved calculations, history, and favorites;
- provide and verify Pro features and purchases;
- diagnose crashes and technical problems;
- understand application usage and improve CALQENTRA;
- display advertisements in the free version; and
- maintain the security and reliability of the application.
4. Third-Party Services
CALQENTRA may use third-party services to provide authentication, cloud storage, application functionality, analytics, crash reporting, advertising, and Google Play purchase processing.
These services may include:
- Google Firebase
- Firebase Authentication
- Cloud Firestore
- Firebase Analytics
- Firebase Crashlytics
- Google AdMob
- Google Play Billing
- Google Sign-In
These providers may process information according to their respective privacy policies and terms.
5. Data Storage and Security
We use reasonable technical and organizational measures intended to protect information against unauthorized access, alteration, disclosure, or destruction.
However, no electronic storage or transmission system can be guaranteed to be completely secure.
6. Data Retention
Account and application data may be retained for as long as necessary to provide CALQENTRA's services and maintain the user's account.
When an account deletion request is completed, associated account data will be deleted in accordance with the applicable deletion process, except where retention is required or permitted for legitimate purposes such as legal, security, fraud-prevention, accounting, or regulatory requirements.
Certain purchase, transaction, security, or diagnostic records may be retained by third-party service providers according to their own policies and legal obligations.
7. Account Deletion
If you have created a CALQENTRA account and want it deleted, you may request account deletion by contacting us at:
Shandexpro@gmail.com
Please replace the email address above with the CALQENTRA support email address before publishing this page.
Your request should clearly state that you want your CALQENTRA account deleted.
After verifying the request where necessary, we will process the deletion of the account and associated user data in accordance with our applicable policies and legal obligations.
8. Children's Privacy
CALQENTRA is an engineering and technical application and is not specifically directed toward children.
We do not knowingly collect personal information from children in violation of applicable laws.
9. Changes to This Privacy Policy
We may update this Privacy Policy from time to time to reflect changes to CALQENTRA, our services, applicable laws, or our data practices.
When changes are made, the updated policy will be published at this webpage with an updated effective date.
10. Contact
If you have questions about this Privacy Policy, CALQENTRA, or your personal information, please contact us at:
Shandexpro@gmail.com
11. Effective Date
Effective date: September 26, 2026