Privacy Policy for DualBook

Effective Date: May 25, 2026

Last Updated: May 25, 2026

Welcome to DualBook, a local-first business and personal finance ledger application operated by Luminexy. Your privacy is our core priority. This Privacy Policy outlines how we handle your information when you use our application.

1. Zero-Server Commitment

DualBook follows a strict "Zero-Server" policy. All your income, expenses, stock, and ledger records are stored exclusively on your device's local storage. We do NOT collect, save, or store any of your private or business data (including names, phone numbers, or transactions) on our servers or any online database.

2. Information Collection & Use

The app does not require account registration or sign-in. Your name, phone number, and address are never stored online. To maintain the app and keep features free, we use third-party services like Google AdMob and Firebase. These may collect technical identifiers (like Advertising ID) to improve app stability and experience, but they never have access to your private financial records.

3. Log Data

Whenever you use our service, in case of an error in the app, we collect data and information (through third-party products) on your phone called Log Data. This may include your device IP address, device name, operating system version, and the configuration of the app when utilizing our service.

4. Cookies

Cookies are anonymous unique identifiers. This service does not use these "cookies" explicitly. However, the app may use third-party code and libraries (like Google AdMob) that use "cookies" to collect information and improve their advertising relevance and service quality.

5. Service Providers

We employ third-party companies (Google Play Services, Firebase Analytics, AdMob) to facilitate our service or analyze usage. These third parties have access to technical identifiers only to perform specific tasks and are obligated not to disclose or use them for any other purpose.

6. Connectivity Disclosure

DualBook allows you to view all existing records and reports perfectly in offline mode. However, an active internet connection is mandatory to add new transactions, edit, or modify records. This requirement ensures app integrity, real-time security validation, and the sustainability of the application.

7. Security

We value your trust in providing us your information, thus we are striving to use commercially acceptable means of protecting it. But remember that no method of electronic storage or transmission over the internet is 100% secure, and we cannot guarantee its absolute security.

8. Links to Other Sites

This service may contain links to other sites (like advertisements). If you click on a third-party link, you will be directed to that site. Note that these external sites are not operated by us; therefore, we strongly advise you to review their Privacy Policy.

9. Data Backup & Recovery

The app utilizes Android Auto Backup, syncing your local data to your personal Google Drive account in an encrypted format. This backup is private between you and Google; the developers have no access to it. You can restore your data easily on a new device using the same Google account.

10. Full Data Ownership & Deletion

As a server-less app, you are the sole owner of your data. You can permanently wipe all records, history, and settings from the device at any time using the "Delete All App Data" feature in settings. Once deleted, the data cannot be recovered.

11. Children's Privacy

These services do not address anyone under the age of 13. We do not knowingly collect personally identifiable information from children under 13. Since all financial data is stored locally, we have no access to any information provided by users, including children.

12. Changes to This Policy

We may update our Privacy Policy from time to time. Thus, you are advised to review this page periodically for any changes. We will notify you of any changes by posting the new Privacy Policy on this page. These changes are effective immediately after they are posted.

13. Contact Us

If youhave any questions regarding this Privacy Policy or your data safety, please contact our support ecosystem at: luminexy.dev@gmail.com