Privacy Policy

1. Who we are

Tokkun: Japanese Drills (“Tokkun,” “the app”) is provided by Nixlight (“we,” “us,” or “our”). Questions about this policy can be sent to [email protected].

2. Information stored on your device

The app stores the following information locally so its features can work:

• practice plans and their settings;
• card review state, schedules, ratings, favorites, mistakes, and mastered status;
• practice totals, durations, and progress history;
• language, theme, premium status, and free-credit balance.

We do not upload this learning history to Firebase or operate a cloud sync service for it. Deleting the app may delete this data unless your device platform preserves or backs it up as part of its own services.

3. Purchases and premium access

Purchases are processed by Apple App Store or Google Play. Tokkun uses RevenueCat to verify purchases and restore Lifetime Premium. RevenueCat receives a randomly generated, pseudonymous app-user identifier together with purchase receipts or purchase tokens, transaction and purchase history, product and entitlement information, app version, platform, locale, and related technical information. We do not provide RevenueCat with your name or email address, and we do not receive your full payment-card details.

Their processing is governed by their own privacy policies and your store account settings. See the RevenueCat Privacy Policy.

4. Rewarded advertising

Free users may choose to watch rewarded ads supplied by Google AdMob to earn practice credits. The Google Mobile Ads SDK processes information such as IP address, device, app-instance and advertising identifiers where available, general location derived from network data, app and ad interactions, diagnostics, fraud-prevention signals, and advertising consent choices. This information may be shared with Google and the ad technology providers listed in the consent message shown for your region. The exact processing depends on your region, device settings, consent choices, and Google’s policies.

Where required, Tokkun uses Google’s User Messaging Platform to present and store advertising choices. On iOS, Tokkun asks free users for App Tracking Transparency permission once after the first launch and before the Mobile Ads SDK is initialized. If permission is declined, Tokkun requests non-personalized rewarded ads. Declining personalized ads or tracking does not prevent the limited processing needed to deliver an ad, measure basic interactions, secure the service, or prevent fraud. Advertising choices can be reviewed from the Get Credits screen when Google requires a privacy-options entry for your region, and the iOS tracking permission can be reviewed in the app’s system settings.

Watching a rewarded ad is optional. Lifetime Premium removes the credit and rewarded-ad entry points from the app. Learn more about how Google uses information from apps that use its services.

5. App analytics

Tokkun uses Firebase Analytics on Android and iOS release builds to understand how app features are used and to improve reliability and product design. Firebase Analytics is enabled when an ordinary release build starts and processes app interactions and screen views, app-instance or device identifiers, device and operating-system information, approximate region, diagnostics, and automatically collected purchase or advertising events where applicable. Tokkun also records coarse feature events such as starting or completing a practice, its category and mode, and aggregate question count. We do not send card text, card answers, detailed learning history, or the text of feedback or an error report to Analytics.

6. Feedback, card error reports, anonymous authentication, and App Check

If you send feedback or use “Found an error,” Tokkun creates a pseudonymous anonymous Firebase Authentication identifier so Firestore security rules can isolate submissions and enforce a shared submission limit. Firebase Authentication also processes IP address and user-agent information for authentication, security, and abuse prevention.

General feedback includes the title and content you enter. A card report includes the stable internal card identifier and any optional note you enter. Both types also include the anonymous identifier, app language, platform, app version, build number, content revision, and submission time. A separate rate-limit record stores the anonymous identifier, the current 24-hour window, last submission identifier and time, and submission count. We use these records only to improve Tokkun, provide support, review or correct content, secure the submission service, and prevent abuse.

Firebase App Check helps reject automated or modified-client abuse. Depending on platform, Google may process integrity attestations and related SDK, application, device, or request information. App Check tokens are not used to identify you by name.

7. Audio, speech, and permissions

Tokkun can play bundled Japanese pronunciation audio and may use your device’s text-to-speech service for Japanese words. Tokkun does not record your voice, evaluate your pronunciation, or request microphone access for its current practice features. A device or operating-system speech service may process text according to that provider’s settings and privacy policy.

8. Support

If you contact support by email, we receive the email address and information you choose to send. We use it to respond and troubleshoot. In-app feedback and card error reports are submitted as described above and do not include your email address.

9. Website data

This website is hosted on Cloudflare Pages. Cloudflare may process basic request and security information, including IP address, user agent, request time, and requested URL, to deliver and protect the site. We do not place marketing cookies or run behavioral analytics on this website.

10. Sharing and retention

We do not sell your personal information. Information is shared only with service providers described above, when you direct us to do so, or when required to comply with law or protect users, rights, and security. We require service providers that receive information from Tokkun to handle it under contractual and legal protections that are consistent with the protections described in this policy.

In-app feedback, card reports, their rate-limit records, anonymous authentication records, and support emails are retained while reasonably needed to review content, resolve requests, prevent abuse, maintain records, and meet legal obligations, or until we approve a valid deletion request. Deleting Tokkun does not by itself delete these cloud records. Firebase may retain authentication and backup data for a limited period after we request deletion. RevenueCat and the app stores retain purchase records as required to verify entitlements, process transactions and refunds, prevent fraud, and meet legal obligations. Firebase Analytics retains event data according to the retention settings applied to our Analytics property; aggregated reports may remain after event-level data expires.

11. Children’s privacy

Tokkun is not directed to children under 13, or the equivalent minimum age in the relevant jurisdiction. We do not knowingly collect personal information from children. If you believe a child has sent personal information to us, contact us so we can take appropriate action.

12. Your choices and rights

• You can avoid rewarded ads by not opening or completing them.
• You can review advertising choices from Get Credits when a privacy-options entry is required for your region, and manage system tracking permission in iOS Settings.
• Tokkun does not currently provide a separate in-app switch for Firebase Analytics collection.
• You can delete local Tokkun data by deleting the app, subject to platform backup behavior.
• You may contact us to request access to or deletion of in-app feedback, a card report, the related anonymous Firebase account and rate-limit record, or information you sent directly to support.

Because Tokkun does not know your name and does not display the anonymous identifier, we may need details such as the card involved, feedback title, approximate submission time, app version, and platform to locate a record. Deleting cloud feedback data does not cancel or erase an App Store or Google Play transaction. Depending on where you live, additional privacy rights may apply. We may ask for information needed to verify and fulfill a request.

13. Changes to this policy

We may update this policy as Tokkun or applicable requirements change. The effective date above identifies the current version. Material changes will be communicated through the app, store listing, or this website when appropriate.