Privacy Policy

RingJapan inc. ("we", "us") sets out how we handle information in our app "Rhythmon" (the "App") and on this website. The App is intended for use by children, and we take care to handle information in a way that lets parents and guardians use it with confidence.
The App is available for iPhone and iPad (distributed on the App Store) and for Android smartphones and tablets (distributed on Google Play). This policy applies to both.
日本語版はこちら

1. Information collected in the App

The App itself is designed to comply with Apple's "Kids" category guidelines and Google Play's Families Policy. We do not ask children to enter, nor do we collect, personal information that identifies a child (such as name, address, or phone number). Favorites, play history, and custom-stage settings are stored only on the device and are not sent to our servers.
The characters' singing voices (rap) are generated on the device using the device's built-in speech synthesis (Apple's speech synthesis on iPhone and iPad, and the device's text-to-speech engine on Android); this data is not sent to us or to any third party.
However, as described below, communication with third-party providers and servers occurs for "Advertising" and "Stage delivery", and certain information may be collected in those cases.

2. Advertising (Kidoz)

In the free version, we may display advertising through "Kidoz" (Kidoz Ltd.), an ad service designed for child-directed apps that complies with Apple's "Kids" category and applicable laws, and is one of Google Play's Families Self-Certified Ads SDKs.

For details on the information Kidoz collects and uses, please see the Kidoz Privacy Policy (https://kidoz.net/privacy-policy/). These practices are also reflected in the "App Privacy" section on the App Store and the "Data safety" section on Google Play. Subscribing to the paid plan (JPY 310 / month) removes advertising.

3. Downloading new stages

The App may receive new stage data over the internet. This delivery uses the cloud service "Supabase", and communication records such as IP addresses may be retained on the delivery server. These are standard records used for delivery and abuse prevention; we do not transmit any information that identifies a child.

4. Information collected via inquiries

When you use the contact form on this website, you provide your name and email address. We use this information solely to respond to your inquiry; we do not use it beyond that purpose or provide it to third parties. After we have finished responding, information is deleted appropriately once it is no longer needed.

5. For parents and guardians (inquiries and deletion requests)

For questions about your child's information, or to request confirmation or deletion of information we hold, a parent or guardian may contact us through the contact form. We will review and respond appropriately.

6. Purchases and external links

In-app purchases and links to external sites are placed behind a "parental gate" that confirms an adult is operating the device. Payments are processed through Apple's App Store on iPhone and iPad, and through Google Play on Android; we do not retain payment information. You can manage or cancel the paid plan in your App Store account settings or in "Payments & subscriptions" on Google Play.

7. Operator information / Contact

Operator: RingJapan inc.
Address: Star Bldg. 7F, 1-5-6 Shinsakae, Naka-ku, Nagoya-shi, Aichi 460-0007, Japan
Email: info@ml.rja.co.jp
Contact: contact form

8. Changes to this policy

We may change this policy as necessary. Any changes take effect when posted on this page.

Effective date: September 28, 2026
Last updated: October 2, 2026 (added Android / Google Play, the Advertising ID, and on-device speech synthesis)

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