Privacy Policy

Last updated: October 20, 2026

MRCY ("Developer") establishes this Privacy Policy ("Policy") regarding the handling of personal information in the iOS application "Chuju Hamutore" (formerly "Chuju Tore") ("App").

Article 1 (Personal Information)

"Personal information" refers to personal information as defined under the Act on the Protection of Personal Information — information about a living individual that can identify a specific person through descriptions such as name, date of birth, address, telephone number, or other contact details, and information that can identify a specific individual on its own (personal identification information).

Article 2 (Collection of Personal Information)

The App does not require account registration and does not provide fields for entering names, email addresses, phone numbers, or similar information. The underlying study data, including learning history, scores, progress, answer records, and settings, is stored on the user's device and is not stored on servers operated by the Developer. In versions that support iCloud sync, if the user is signed in to iCloud, study data is also stored in the user's own iCloud (a private storage area provided by Apple) and synced across devices using the same Apple Account. The Developer cannot view this data. However, limited aggregate values derived from study activity, such as subject, category, question count, correct count, accuracy, and study duration, are transmitted to third-party services as usage data described below.

For product improvement, diagnostics, and subscription management, the App may collect the following limited information through third-party services:

• Usage data: app launches, grade and subjects selected during onboarding, subjects, units and steps used, question counts, correct counts and accuracy, study duration, learning streaks, paywall entry points, purchase outcomes, and settings changes
• Content issue reports: when the user sends one, the identifiers of the question or unit and the selected reason (there is no free-text field)
• Diagnostic data: crash logs, stack traces, app state, device, OS and app version information, and fixed diagnostic codes identifying an affected feature
• Purchase data: product identifiers, purchase, renewal, cancellation and restoration status, active subscription status, and an anonymous app user identifier
• Service-generated identifiers: Firebase Installation ID, Analytics App Instance ID, Crashlytics Installation UUID, and similar identifiers

The App does not transmit question text, answers entered by the user, names, contact details, or the advertising identifier (IDFA). Study reminders, widgets, and Siri/Shortcuts run on the device and do not send information to the Developer.

Article 3 (Purpose of Collection and Use)

The collected information is used only to:

• Aggregate App usage and improve features and usability
• Detect crashes and defects and investigate and correct their causes
• Display subscription products, process purchases and restorations, and verify access rights
• Prevent abuse, maintain security, and respond to support inquiries

The Developer does not use this information for advertising, advertising attribution, or profiling by combining it with third-party data.

Article 4 (Changes to Purpose of Use)

1. The Developer will change the purpose of use of personal information only when it is reasonably recognized as having a relevant connection to the purpose before the change.
2. When a change of purpose occurs, the updated purpose will be communicated to users via the App's update notes or this page.

Article 5 (Third-Party Services)

The App uses the following third-party services. Information handled by each service is governed by that provider's privacy policy and terms.

• Google Firebase Analytics: aggregation of usage data
• Google Firebase Crashlytics: collection of crash and diagnostic data
• RevenueCat: management of subscription status, purchase history, and access rights
• Apple: App Store payment processing and purchase transactions, and syncing study data via iCloud (CloudKit) using the user's own iCloud

Apple processes payment information. Neither the Developer nor RevenueCat receives credit card numbers or similar payment credentials. Except where required by law, the Developer does not provide collected information to advertising companies or data brokers.

Article 6 (Disclosure of Personal Information)

Requests for disclosure may be submitted through the contact method in Article 11. However, because the App does not use accounts and the Developer does not associate third-party service identifiers with names or contact details, the Developer may be unable to identify information corresponding to a particular user.

Article 7 (Correction and Deletion of Personal Information)

Study data stored on the device can be deleted through the App's settings screen or by uninstalling the App. Study data stored in iCloud can be deleted from the Apple Account (iCloud) storage management in the device's Settings. To request deletion of information already transmitted to third-party services, please use the contact method in Article 11. Requests will be handled in accordance with applicable law and the capabilities and retention periods of each service.

Article 8 (Suspension of Use of Personal Information)

Uninstalling the App deletes on-device study data (study data stored in iCloud remains and is restored when the App is reinstalled) and stops future transmission of usage and diagnostic data. Information already transmitted is deleted or anonymized after the period necessary for the stated purposes or the retention period established by each third-party service.

Article 9 (Children's Privacy)

The App is a learning app intended to be used by children. It does not require account registration or the entry of names or contact details, does not display advertising, and does not collect IDFA. Question text and answers are not transmitted, and Firebase and RevenueCat identifiers are not linked to each other. Guardians can manage their child's use through device settings and Screen Time.

The App does not engage in tracking as defined by Apple.

Article 10 (Changes to Privacy Policy)

1. The content of this Policy may be changed without notifying users, except as required by law or otherwise specified in this Policy.
2. The revised Privacy Policy takes effect when posted on this page. Changes that materially affect users' rights will be communicated via the App's update notes in advance.

Article 11 (Contact)

For inquiries regarding this Policy, please contact us via the "Contact" option in the App's settings screen or through the contact form.

Developer: MRCY