Privacy Policy

The HA NOI DOOR TRADING AND SERVICE PRODUCTION JOINT STOCK COMPANY Apps are created by HA NOI DOOR TRADING AND SERVICE PRODUCTION JOINT STOCK COMPANY., a limited liability company under Vietnamese law.

This Privacy Policy is compliant with the General Data Protection Regulation (GDPR 2016/679). HA NOI DOOR TRADING AND SERVICE PRODUCTION JOINT STOCK COMPANY is an App development and app publishing company. We deliver Apps to almost all app stores all over the world. We create Apps for many different devices including but not limited to phones, tablets, watches, TVs, etc. By using the App, you are consenting to our processing of data as outlined in this Privacy Policy. Our terms for the use of Apps (which can be found here http://terms) apply to your use of the Apps.

1. What data do our Apps obtain?

1.1 Data we collect

• Device and usage data: device model, OS version, language, IP address, and in-app usage events (such as lessons opened and quizzes completed), collected through Firebase Analytics.
• Study progress: your selected state, license type, exam date, study profiles, quiz and practice-exam results, and saved questions.
• If you choose to sign in: the Apple or Google user identifier and your email address (Apple's private relay address is accepted).
• If you allow tracking: the device advertising identifier (IDFA), used by Adjust for campaign attribution.
• If you contact us or report a question error: the content of your message.

We do not collect precise location, passwords, your name, profile photo, contacts, or payment information.

2. Data Sharing and Advertising

• 2.1 We use your data only to provide and improve the App, to restore your progress on a new device, and to measure which marketing campaigns bring new users.
• 2.2 THIS APP CONTAINS NO ADVERTISING
  This App displays no advertising and does not share data with advertising networks for the purpose of serving ads. The advertising identifier is used only to measure which marketing campaigns bring new users to the App, and only with your permission (see "Tracking and App Tracking Transparency").
• 2.3 Third-party services. We use Google Firebase (Analytics and Remote Config) to understand how the App is used and to configure features; Adjust to measure marketing campaign attribution (only with your permission on iOS); and Apple and Google sign-in, only if you choose to sign in. These providers process data under their own privacy policies.

3. Managing Your Data

• 3.1 You can stop all collection of data by the App easily by uninstalling the App. You may use the standard uninstall processes as may be available as part of your device or via the application marketplace or network.
• 3.2 Tracking choices. On iOS you can allow or deny tracking when the App first asks, and change your choice at any time in Settings > Privacy & Security > Tracking.
• 3.3 The NAI and the Digital Advertising Alliance (DAA) offer opt-out tools to assist you in managing your choices for participating companies. For more data about these tools, please visit: http://networkadvertising.org/choices/ or https://aboutads.info
• 3.4 TRACKING AND APP TRACKING TRANSPARENCY (iOS)

  We use an attribution tool to measure which marketing campaigns bring new users to the App. This involves the advertising identifier (IDFA) on your device.

  On iOS, we ask for your permission through Apple's App Tracking Transparency framework before any such data is collected. The request appears when you first open the App, at the start of the onboarding flow.

  If you decline, we do not access your advertising identifier and do not use it for attribution. The App remains fully functional either way — no feature depends on your answer, and we offer no reward for agreeing.

  You can change your decision at any time in your device settings: Settings → Privacy & Security → Tracking.

  We use this data only to understand how people discover the App. We do not sell your data, we do not share it with data brokers, and the App shows no advertising.

4. Business Transfers

Data about you may be disclosed as part of any merger, acquisition, or sale of company assets. In the unlikely event of an insolvency, bankruptcy, or receivership, your data may also be transferred as a business asset.

5. Children

We do not use the Apps to knowingly solicit data from or market to children under the age of 13. If a parent or guardian becomes aware that his or her child has provided us with data without their consent, he or she should contact us at reninsai1@gmail.com. We will delete or anonymize such data from our files within a reasonable time.

6. Security

We are concerned about safeguarding the confidentiality of your personal data. We provide physical, electronic and procedural safeguards to protect data we process and maintain. For example, we limit access to this data to authorized employees and contractors who need to know that data in order to operate, develop or improve our Apps. Please be aware that, although we endeavour to provide reasonable security for personal data we process and maintain, no security system can prevent all potential security breaches. As stated above, we use anonymization techniques in order to limit the use of personally identifiable information as much as possible.

7. Data retention

We keep study progress and account data while your account exists. Deleting your account in the App permanently deletes this data. Analytics data is kept for up to 12 months and then aggregated. If you have not signed in and want your data deleted, contact reninsai1@gmail.com and we will respond within 30 days.

8. Changes

This Privacy Policy may be updated from time to time. We will notify you of any changes to our Privacy Policy by posting the new Privacy Policy here. You are advised to consult this Privacy Policy regularly for any changes. If you have any questions, please contact us at reninsai1@gmail.com. This Privacy Policy was updated on 1st October 2026.

9. Account and Sign-in

10. Deleting