Privacy Policy

1. Information handled on the device

The App processes the following information on the user's device to provide its features and does not send it to servers managed by the Operator. This information can be deleted through in-App controls, device settings, or by deleting the App.

• Vocabulary cards, study progress, and completed books
• Learning-mode, playback, and card-display settings
• Notification settings
• Onboarding completion status

2. Information handled through external services

The App may handle the following information through external services for advertising and inquiry handling.

• Advertising identifiers when their use is authorized, device information, IP addresses and approximate location inferred from them, ad interaction data, identifiers used to deliver ads, and diagnostic information such as crash logs and performance data, as processed by Google AdMob
• The sender's email address, display name, message, and information included in attachments received through email inquiries
• Category, message, public app ID, submission ID, time received, and handling status collected through anonymous feedback

3. External services and international processing

The Operator uses the external services listed below. These providers may process information in the United States or other countries outside Japan. The Operator reviews their contractual terms and privacy safeguards and requires protections necessary under applicable law and this policy. Except where required by law, the Operator does not provide information to third parties beyond what is necessary for the stated purposes. You may request information about international processing and relevant safeguards through the contact channel in section 12.

• Google (Google AdMob and inquiry email): ad delivery, ad measurement, and inquiry handling (https://policies.google.com/privacy)
• Cloudflare (Pages, Workers, D1, and Turnstile): delivery of related pages, feedback storage, and automated-submission protection (https://www.cloudflare.com/privacypolicy/)

4. Purposes of use

• To provide and operate the App and related services
• To display vocabulary cards, play audio, and manage progress on the device
• To deliver study-reminder notifications
• To deliver advertising and measure ad performance
• To improve advertising-service stability and performance and prevent fraud
• To handle feedback and inquiries

5. App Tracking Transparency (ATT)

On iOS 14.5 and later, the App requests permission under App Tracking Transparency (ATT) before tracking by linking information from the App with information from other companies' apps or websites, or accessing the advertising identifier (IDFA). ATT permission does not replace any separate consent for advertising required by applicable law or in a particular region.

• If you allow tracking, the advertising identifier may be used for personalized ads and ad measurement
• If you do not allow tracking, you can still use the App. Displayed ads may be less relevant. Google AdMob may still process IP addresses, device information, and information other than the IDFA as necessary to deliver non-personalized or limited ads, prevent fraud, maintain security, or perform basic measurement
• You can change this later in iOS Settings > Privacy & Security > Tracking

6. Feedback that does not request direct identifiers

The Service's feedback form does not request a name, address, phone number, or email address as an input field, but it receives the information listed below. If you enter personal information about yourself or another person in the free-text field, the Operator and Cloudflare will also process that information. Do not enter personal information.

• Feedback category and message
• A public app ID identifying the applicable App
• A submission ID used to prevent duplicate submissions
• Time received and handling status

7. Feedback from the App

Feedback from the App is submitted through the Service's anonymous feedback form. The App does not request a name, email address, or other contact details as input fields. The information handled is as described in section 6.

8. Feedback storage, automated-submission protection, and retention

Website feedback is stored in Cloudflare D1. The Operator uses Cloudflare Turnstile to prevent automated submissions. Turnstile processes browser-environment and other signals necessary for fraud detection, and its verification token is sent to Cloudflare's Siteverify API. The Operator does not send the feedback message or other form fields to the Siteverify API and does not store Turnstile tokens or verification results in its database.

Information concerning feedback and email inquiries is retained for as long as necessary to respond and fulfill the other stated purposes. Information that is no longer needed is periodically deleted. However, information needed to meet legal obligations or handle disputes is retained for as long as necessary for those purposes. Information and backups retained by external providers are also subject to their respective retention and deletion policies.

9. Children

The Service is not directed to children under 13. If the Operator learns that it has obtained personal information from a child under 13, the Operator will promptly delete information that it can identify, unless retention is required by law. A parent or guardian may contact the Operator using the channel in section 12.

10. Security, user rights, and request procedure

The Operator applies access controls, permission management, and other necessary and appropriate safeguards. Subject to applicable law, users may request access to, correction of, restriction of, deletion of, or cessation of third-party disclosure of information about themselves. Submit a request through the channel in section 12 and provide information necessary to identify the relevant data. The Operator will verify the requester's identity and respond in accordance with applicable law. If the Operator cannot fulfill the request, it will explain the reason. The Operator will give advance notice of any applicable fee.

In-App study data, settings, and notifications can be deleted through available in-App controls, device settings, or by deleting the App. Because the website feedback form does not request direct identifiers, the Operator may be unable to identify the requester or locate the relevant submission.

11. Changes to this policy

The Operator may update this policy when the Service, external services, or applicable law changes. Material changes will be announced in the App or on related pages with reasonable advance notice. The Operator will obtain consent where applicable law requires it.

12. Operator information and contact

For questions or requests concerning this policy, international processing, safeguards, or user rights, email isajiappdev@gmail.com. The Operator will, upon a data subject's request and without undue delay, provide the Operator's legal name and address and, if the Operator is a corporation, the name of its representative, to the extent disclosure is required by law.