English Root Words Privacy Policy

English Root Words (the "App") is a vocabulary learning app provided by Sho Fujimoto (the "Developer") that helps users write English words, generate root-based explanations, save words to a wordbook, play audio, and review saved words.

This Privacy Policy explains how information is handled in connection with the App.

1. Information We Collect or Use

The App may collect or use the following information.

1.1 Information You Enter or Configure

• English words selected or entered for root generation
• Handwriting input, recognized text candidates, and related recognition results
• App language, audio settings, review settings, and other preferences
• Wordbook import files and exported wordbook data that you choose to handle in the App

1.2 Learning Data Generated in the App

• Generated root explanations, meanings, examples, and related learning content
• Saved words, wordbook entries, and review history
• Flashcard results, memory-check results, review timing, and learning counters
• Audio model download state and local audio-related settings

Much of this information is stored locally on your device. Local data may be lost if you delete the App, reset your device, change devices, or due to operating system or device behavior.

1.3 Information Collected Automatically

• Device information, operating system information, and App version
• Language and region settings
• Advertising identifiers such as IDFA and AAID
• Ad impressions, clicks, and measurement information
• Technical information such as communication logs, error logs, usage data, and abuse-prevention logs

1.4 Subscription-Related Information

Purchase information related to the App's subscription (English Root Words Pro) is processed through the Apple App Store or Google Play Store. The Developer uses RevenueCat (RevenueCat, Inc.) to manage subscription state. As a result, the following information may be handled:

• Purchase status, subscription expiration date, and auto-renewal state
• Receipts and transaction identifiers issued by the store
• An anonymous user ID per device or installation used by RevenueCat to identify users

The Developer does not directly collect or store payment details such as credit card numbers, bank account information, or passwords. Payment information is processed by Apple and Google through their respective stores.

2. How We Use Information

We use information for the following purposes:

• To recognize handwritten words and provide vocabulary learning features
• To generate root explanations, meanings, examples, and related learning content
• To save and display your wordbook, review history, settings, and learning progress
• To provide flashcards, memory checks, review timing, import, export, and audio playback
• To investigate bugs, improve quality, improve App features, and prevent abuse
• To deliver ads, measure ad performance, and prevent ad fraud
• To provide and manage the subscription service, including state management and purchase restoration
• To comply with laws, terms, and platform policies

3. AI Features

To generate root explanations, meanings, examples, or other learning content, the App may send selected words, language settings, and related request information to the Developer's servers and AI service providers.

This information is processed for generation, quality improvement, safety, abuse prevention, and troubleshooting. The Developer does not store your full wordbook on servers for the purpose of permanent retention, but communication logs, error logs, and security-related logs may be temporarily recorded.

Do not enter sensitive personal information into word input, import files, or other text fields, including your real name, address, phone number, email address, credit card information, passwords, health information, or other confidential information.

4. Local Storage and Import/Export

Saved words, generated learning content, review records, settings, and some usage counters are primarily stored on your device using local storage. The App may allow you to export or import wordbook data. You are responsible for managing exported files and for ensuring that files you import do not contain personal, confidential, illegal, or rights-infringing content.

5. Ads and Tracking

The App may use third-party advertising services such as Google AdMob. These services may collect or use advertising identifiers, device information, ad impression and click data, approximate location, and related information for ad delivery, ad measurement, fraud prevention, and personalized advertising.

On iOS, advertising identifiers may be used for tracking across apps and websites only if you grant permission through App Tracking Transparency. If you do not grant permission, you can still use the App's core features, but ads may be less relevant.

You may be able to manage ad personalization through your operating system, device settings, Google account settings, or settings provided by advertising services.

6. Third-Party Services

The App may use the following third-party services:

• Google AdMob / Google Play services
• Expo
• AI service providers
• RevenueCat (subscription state management)
• Apple App Store / Google Play Store (payment and subscription processing)
• Cloud hosting, logging, security, and abuse-prevention services

These third-party services handle information in accordance with their own privacy policies.

References:

• Google Privacy Policy: https://policies.google.com/privacy
• Google AdMob: https://support.google.com/admob/answer/6128543
• Expo Privacy Policy: https://expo.dev/privacy
• RevenueCat Privacy Policy: https://www.revenuecat.com/privacy
• Apple Privacy Policy: https://www.apple.com/legal/privacy/

7. Advertising Partners and Users in the EEA / UK / Switzerland

This App may serve ads via Google AdMob with consent-management features. As a result, advertising identifiers, IP address, device information, and related information may be shared with advertising partners for ad delivery and measurement. The current list of partners may be available inside the consent dialog shown in the App and at:

• AdMob ad technology providers: https://support.google.com/admob/answer/9012903
• IAB TCF vendor list: https://iabeurope.eu/vendor-list-tcf/

If you live in the European Economic Area (EEA), the United Kingdom, or Switzerland, the GDPR / UK GDPR grant you rights such as access, rectification, erasure, restriction of processing, data portability, objection, and withdrawal of consent. To exercise these rights, contact us using the contact information at the end of this policy. If a consent dialog is available in the App, you can withdraw or change your consent through that dialog.

On iOS, App Tracking Transparency (ATT) requires your permission before the App can use your IDFA to track you across apps and websites. You can use the App without granting permission, though ads may be less relevant.

8. Retention

Learning data stored on your device may remain until you delete it in the App, uninstall the App, or it is removed by your device or operating system.

Logs and other information processed on servers are retained only for as long as reasonably necessary for the purposes described in this Privacy Policy and then deleted or anonymized, unless a longer retention period is necessary for legal compliance, security, abuse investigation, or dispute resolution.

9. Sharing With Third Parties

The Developer does not sell your personal information. The Developer may share or transmit information in the following cases:

• With your consent
• When necessary to provide the App through AI services, advertising services, subscription services, infrastructure providers, or other service providers
• When required by law
• When necessary to respond to abuse, security issues, or rights violations
• In connection with a business transfer, merger, or succession

10. Children

The App is not intended for children under 13. Children under 13 must not use the App. If a minor uses the App, they should do so with consent and supervision from a parent or guardian.

11. Your Controls

You may be able to manage permissions such as advertising identifiers, tracking permission, notifications, network access, and storage through your device settings. You can also delete locally stored App data by uninstalling the App.

However, backups, operating system behavior, and third-party service retention periods may prevent all information from being deleted immediately.

12. Security

The Developer takes reasonable measures to protect information from leakage, loss, damage, unauthorized access, and other security risks. However, no internet transmission or device storage method is completely secure.

13. Changes to This Policy

The Developer may update this Privacy Policy in response to changes in laws, App features, or third-party services. Important changes will be announced through the App, website, or other appropriate methods.

14. Contact

If you have questions about this Privacy Policy, please contact:

• Developer: Sho Fujimoto
• Email: zero@zerotoone.app