Privacy Policy — Nihongo Journey

Effective Date: May 17, 2026 | Last Updated: May 17, 2026 | Package: com.nihongo.app

1. Introduction

Nihongo Journey is a Japanese language learning application for Android. This Privacy Policy explains what personal data we collect, why we collect it, how we use and protect it, and your rights regarding your data.

By using Nihongo Journey, you agree to the practices described in this policy.

2. Data We Collect

2.1 Account Information

Email address — used to identify your account and send password reset emails
Display name — shown in your profile (optional)
Authentication provider — email/password or Google Sign-In
Account creation date and last login timestamp

2.2 Learning Progress Data

JLPT level progress (N5–N1) per module
Completed lesson records and quiz scores
XP, level, and study streak
Bookmarked kanji, vocabulary, and grammar
Weekly activity data

Stored locally in a Room database and synced to Firebase Firestore under your user account.

2.3 Study Plans and Notes

Study plan titles, tasks, notes, schedule entries, and uploaded study files (if you use these features).

2.4 Uploaded Files

Files you upload are stored in Firebase Storage at users/{uid}/study_files/. Only you can access your files.

2.5 Subscription Data

Subscription status is stored server-side. We do not store payment card details — purchases are handled entirely by Google Play Billing.

2.6 Device and Technical Data

Firebase Analytics: Aggregated, anonymized usage events
Firebase Crashlytics: Crash reports (device model, OS version, stack traces — no PII)
Firebase Cloud Messaging: Device token for push notifications
Google Play Integrity: App tamper detection — no personal data collected

2.7 Data We Do NOT Collect

We do not collect location, contacts, camera/microphone access, biometric data, or payment card numbers.

3. How We Use Your Data

Purpose	Data Used
Provide app features	Account info, learning progress
Sync progress across devices	Learning progress, preferences
Send study reminders	FCM token, notification preferences
Verify premium subscription	Subscription status
Improve app stability	Crash reports
Understand feature usage	Analytics events

4. Authentication

Email/Password: Handled by Firebase Authentication. Your password is never stored by us — Firebase stores a secure hash only.

Google Sign-In: We receive your Google email, display name, and a unique user ID. We do not receive your Google password. Google's use of your data is governed by Google's Privacy Policy.

5. Third-Party Services

Service	Provider	Purpose
Firebase Authentication	Google LLC	User login
Firebase Firestore	Google LLC	Cloud data storage
Firebase Storage	Google LLC	File storage
Firebase Analytics	Google LLC	Usage analytics
Firebase Crashlytics	Google LLC	Crash reporting
Firebase Cloud Messaging	Google LLC	Push notifications
Google Play Billing	Google LLC	Subscription payments
Google Sign-In	Google LLC	Social authentication

All Firebase services are governed by Firebase's Privacy Policy.

6. Data Storage and Security

All data in transit is encrypted using TLS (HTTPS). Cleartext HTTP is blocked.
Firestore and Storage are protected by security rules — only you can access your data.
Your data is stored under your unique user ID and is inaccessible to other users.
allowBackup="false" prevents Android system backups from exposing your data.
Release builds use R8 code obfuscation.

Data Retention

Data is retained as long as your account is active.
After account deletion, all data is permanently deleted within 30 days.
Crash reports retained 90 days (Firebase default).
Analytics data retained up to 14 months (Firebase default).

7. Account Deletion

You can delete your account at any time from within the app:

Settings → Account → Delete Account

When you delete your account, all Firestore data, uploaded files, and your Firebase Auth account are permanently deleted. Local data is also cleared from your device.

Note: Active subscriptions must be cancelled separately in Google Play Store → Subscriptions.

You may also request deletion by emailing: nihongo.journey.contact@gmail.com

8. Push Notifications

The app may send daily study reminders and streak reminders. You can disable these at any time in App Settings → Notifications or in Android system settings.

9. Children's Privacy

Nihongo Journey is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child under 13 has provided us with personal information, contact us and we will delete it promptly.

10. Your Rights

Access: Request a copy of your data
Correction: Request correction of inaccurate data
Deletion: Delete your account and all data (see Section 7)
Portability: Request your data in a portable format
Withdraw consent: Disable analytics or notifications at any time

To exercise these rights, contact: nihongo.journey.contact@gmail.com

11. Changes to This Policy

We may update this policy from time to time. We will update the "Last Updated" date and notify you through the app for material changes.

12. JLPT Disclaimer

Nihongo Journey is an independent learning application. It is not affiliated with, endorsed by, or connected to the Japan Foundation, JEES, or any official JLPT examination body.

Contact Us
Email: nihongo.journey.contact@gmail.com
Response time: Within 30 days

Last updated: May 17, 2026