1. Introduction
Steven Huang ("we," "us," or "our") operates the SandTrace mobile application (the "App"). This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our App.
Please read this Privacy Policy carefully. By using the App, you agree to the collection and use of information in accordance with this policy.
2. Information We Collect
2.1 Information Collected Automatically
When you use our App, we may automatically collect the following types of information:
- Device Information: Device model, operating system version, unique device identifiers, and mobile network information.
- Advertising Identifiers: Your device's advertising identifier (e.g., Google Advertising ID on Android, IDFA on iOS) for the purpose of serving personalized advertisements. On iOS 14.5 and later, we request your permission through Apple's App Tracking Transparency (ATT) framework before accessing this identifier.
2.2 Locally Stored Data
The App stores the following data locally on your device only:
- App Preferences: Settings such as selected language and simulation preferences, stored via the device's local storage (SharedPreferences/UserDefaults).
- Saved Simulations: Particle simulation snapshots that you save are stored locally on your device.
- Exported Media: Screenshots and videos you create within the App are saved to your device's photo library with your permission.
This locally stored data is never transmitted to our servers or any third party.
2.3 Information We Do NOT Collect
SandTrace is an offline particle simulation app. We do not require account creation, login, or any form of registration. We do not collect:
- Personal information such as your name, email address, or phone number
- Location data (GPS or IP-based)
- Contacts, calendar, or health data
- Audio, microphone, or camera input
- Biometric data
3. How We Use Your Information
We use the limited information we collect to:
- Display advertisements: We use advertising identifiers to serve ads within the App through Google AdMob.
- Improve the App: We may use aggregated, non-identifying information to understand general usage patterns and improve the App experience.
4. Third-Party Services
Our App uses the following third-party services that may collect information:
4.1 Google AdMob
We use Google AdMob to display advertisements within the App. AdMob may collect device information and advertising identifiers to serve personalized or non-personalized ads based on your preferences and consent.
Privacy Policy: https://policies.google.com/privacy
4.2 App Tracking Transparency (iOS)
On iOS devices running version 14.5 or later, the App will request your permission to track your activity across other companies' apps and websites via Apple's App Tracking Transparency framework. You may choose to allow or deny this request. If you deny the request, you will still see ads, but they will not be personalized based on your cross-app activity.
You can change your tracking preference at any time in your device's Settings > Privacy & Security > Tracking.
5. Data Sharing and Disclosure
We may share your information in the following limited circumstances:
- Advertising Partners: Device advertising identifiers are shared with Google AdMob for the purpose of serving advertisements. No personally identifiable information is shared.
- Legal Requirements: When required by law, regulation, legal process, or governmental request.
- Business Transfers: In connection with a merger, acquisition, or sale of assets, your information may be transferred as part of the transaction.
We do not sell your personal information to any third party.
6. Data Storage and Security
- Local Storage Only: All user-created content (simulations, preferences) is stored exclusively on your device. We do not operate servers that store your personal data.
- Third-Party Data: Information collected by Google AdMob is handled according to Google's own data storage and security practices. Please refer to Google's Privacy Policy for details.
7. Data Retention
Since we do not collect or store personal data on our servers, there is no server-side data retention to manage. Locally stored data (preferences, saved simulations) remains on your device until you delete it or uninstall the App.
Advertising data collected by Google AdMob is retained according to Google's data retention policies.
8. Children's Privacy
Our App is not specifically directed at children under the age of 13. We do not knowingly collect personal information from children under 13. Since our App does not require account creation and does not collect personal information, no age verification is necessary. However, advertisements displayed by Google AdMob are configured to comply with applicable regulations regarding minors.
If you are a parent or guardian and believe your child has been exposed to inappropriate advertising content through our App, please contact us so we can take appropriate action.
9. Your Rights
9.1 For All Users
You have the right to:
- Control ad tracking: Opt out of personalized advertising through your device settings or the ATT prompt on iOS.
- Reset advertising ID: Reset your device's advertising identifier at any time through your device settings.
- Delete local data: Remove all locally stored data by uninstalling the App.
9.2 European Economic Area (GDPR)
If you are in the European Economic Area, you have additional rights under the General Data Protection Regulation (GDPR):
- Right of Access: You have the right to request a copy of the data we hold about you.
- Right to Rectification: You have the right to request correction of inaccurate data.
- Right to Erasure: You have the right to request deletion of your data ("right to be forgotten").
- Right to Restrict Processing: You have the right to request that we limit the processing of your data.
- Right to Data Portability: You have the right to request a transfer of your data in a structured, machine-readable format.
- Right to Object: You have the right to object to the processing of your data.
- Right to Withdraw Consent: You have the right to withdraw consent at any time.
- Right to Lodge a Complaint: You have the right to lodge a complaint with your local supervisory authority.
Legal basis for processing: We process advertising data based on your consent (GDPR Article 6(1)(a)), which you can withdraw at any time through your device settings.
9.3 California Residents (CCPA/CPRA)
If you are a California resident, under the California Consumer Privacy Act (CCPA) and California Privacy Rights Act (CPRA), you have the right to:
- Know what personal information is collected about you
- Know whether your personal information is sold or disclosed and to whom
- Opt out of the sale of your personal information
- Access your personal information
- Request deletion of your personal information
- Non-discrimination for exercising your privacy rights
We do not sell personal information as defined by the CCPA.
9.4 Taiwan (Personal Data Protection Act)
If you are in Taiwan, under the Personal Data Protection Act (個人資料保護法), you have the right to:
- Request access to your personal data (查詢或請求閱覽)
- Request a copy of your personal data (請求製給複製本)
- Request correction or supplementation (請求補充或更正)
- Request cessation of collection, processing, or use (請求停止蒐集、處理或利用)
- Request deletion of your personal data (請求刪除)
10. Photo Library Access
The App requests access to your device's photo library solely for the purpose of saving screenshots and videos of your particle simulations. We do not access, read, or upload any existing photos or videos from your library. The permission is used exclusively for saving new media created within the App.
11. Changes to This Privacy Policy
We may update this Privacy Policy from time to time. We will notify you of any changes by updating the "Last updated" date at the top of this policy. We encourage you to review this Privacy Policy periodically for any changes. Changes are effective when they are posted on this page.
12. Contact Us
If you have any questions or concerns about this Privacy Policy or our data practices, please contact us: