Privacy Policy — Just Kana

Last updated: March 13, 2026

This Privacy Policy describes how Just Kana ("the App", "we", "us") collects, uses, and protects your information when you use our mobile application. We are committed to safeguarding your privacy and ensuring transparency about our data practices.

1. Data We Collect

Automatic Usage Data

When you use the App, certain data may be collected automatically by our third-party service providers, including:

Device identifiers (advertising ID / IDFA)
IP address (anonymized where possible)
Device type, operating system, and version
App usage patterns and session duration
Crash logs and performance data

User-Provided Nickname

If you choose to participate in the global leaderboard, you may provide a nickname. This nickname is stored on our servers and is publicly visible in the ranking. No email, phone number, or other personal identifiers are required.

Optional Tracking Consent (iOS)

On iOS, the App will request your permission via the App Tracking Transparency (ATT) framework before collecting your advertising identifier. You can deny this request and still use the App normally.

2. How We Use Your Data

Advertising — We display ads through Google AdMob. AdMob may use your device identifier and usage data to serve personalized or contextual advertisements.
Leaderboard — Your nickname and quiz/writing scores are sent to our backend server to maintain the global ranking.
App Improvement — Crash reports and performance data help us identify and fix bugs.
Remote Configuration — We fetch configuration parameters from our server to adjust ad frequency and app behavior without requiring an update.

3. Third-Party Services

The App integrates the following third-party services, each with their own privacy policies:

Advertising

Google AdMob (Google LLC, USA)
Google Privacy Policy

In-App Purchases

Apple App Store / Google Play
Purchases are processed entirely by the platform. We do not collect payment information.

Backend API

Planing Lab (proprietary server)
Stores leaderboard data (nickname, scores, device token). No data is sold to third parties.

4. Data Retention

Your leaderboard data (nickname and scores) is retained as long as your account exists on the leaderboard. You can request deletion at any time by contacting us at the email address listed below.

Advertising-related data is managed by Google AdMob according to their own retention policies.

5. Your Rights

Depending on your jurisdiction (including GDPR and US state privacy laws), you have the right to:

🔍 Access — Know what data we hold about you

✎ Rectify — Correct inaccurate data

🗑 Delete — Request erasure of your data

🔒 Restrict — Limit how we process your data

📦 Portability — Receive your data in a portable format

⛔ Object — Opt out of targeted advertising

🔓 Withdraw Consent — Revoke consent at any time

⚖ Complain — Lodge a complaint with your data protection authority

To exercise any of these rights, please contact us at the email address provided in section 6.

6. Data Controller

The data controller responsible for processing your personal data is the app owner, based in our location. For any privacy-related inquiries or to exercise your rights under applicable data protection laws, you can reach us at [email protected].

7. Opting Out of Personalized Ads

You can opt out of personalized advertising through:

iOS: Settings > Privacy & Security > Tracking — disable tracking for Just Kana
Android: Settings > Google > Ads > Opt out of Ads Personalization
In-App Purchase: Buy the "No More Ads" option to remove all advertisements entirely

8. Children's Privacy

Just Kana is an educational app suitable for all ages. We do not knowingly collect personal information from children under 13 (or under 16 in the EU). If you believe a child has provided personal data, please contact us and we will promptly delete it.

9. Data Security

We implement appropriate technical and organizational measures to protect your data, including HTTPS encryption for all API communications and secure token-based authentication. However, no method of electronic transmission is 100% secure.

10. Changes to This Policy

We may update this Privacy Policy from time to time. Changes will be reflected by the "Last updated" date at the top. Continued use of the App after changes constitutes acceptance of the revised policy.