Privacy Policy
Effective date: August 29, 2026
Last updated: August 29, 2026
Yomoe Studio ("we", "us") sets out below how information is handled in the mobile application "Yomoe Sudoku" (the "App") that we provide.
1. Basic policy
The App requires no user registration (no account) and does not ask you to enter your name, email address, date of birth, or any other information that identifies you. Every puzzle is generated on your own device, and neither your play nor your results are sent to or stored on our servers. The App is fully usable in airplane mode.
2. Information stored only on your device
The following information created and recorded by the App is stored only in the App's private storage area on your device, and we never obtain it.
(1) Play state: the game in progress, progress in each mode, completion status and stars earned, the Daily Challenge calendar and streak
(2) Results and achievements: number of games played and completion rate per mode and difficulty, time records, achievements and trophies earned
(3) App settings: display language, gameplay settings, board theme, purchase status
This information is used only to resume a game, to compile and display your results, and to evaluate achievements within the App.
2-2. Information sent to our servers (feedback)
Only when you send a message through the App's "Feedback" feature is the following information sent to and stored on our servers. This happens only after you enter the content and perform the send action; the App does not otherwise transmit your play data to us.
(1) Category (bug report / suggestion)
(2) The text of your feedback
(3) Email address (optional; you can send without it)
(4) Environment information: package name, app version, device model name, OS version (sent blank if it cannot be obtained)
We use this information only to investigate problems, to improve the App, and to reply to you if you provided an email address. We do not use it for advertising or any other purpose, and we do not provide it to third parties except as required by law. Please do not include personal information you do not wish to disclose, such as your name or address, in the body of your feedback.
3. Access to device features
The App does not request access to the camera, photo library, microphone, contacts, location (GPS), or files.
Note that on iOS, as required by Apple, the App's information declares a purpose for "location (while in use)" because an SDK used for advertising may reference that capability. The App itself never obtains or uses your location. If a permission dialog appears, the App behaves identically whether you allow it or not.
4. Data backup
The App can export your play state and settings as a single text string. Export happens only when you choose to perform it, and you decide where to keep or share that string. We do not obtain its contents and are not responsible for how it is handled wherever you share it. The exported string contains no information that identifies you.
5. Third-party services
The App uses the third-party services below. Their handling of information is governed by each company's own privacy policy.
(1) Google AdMob (advertising)
The App displays ads so that it can be offered free of charge. For ad delivery, advertising identifiers (IDFA on iOS, AAID on Android), device information, approximate location (region derived from IP address), and ad impression and interaction history may be collected and used by Google LLC and its advertising partners.
- On iOS, a tracking permission dialog is shown. If you choose "Ask App Not to Track", the App behaves exactly the same and non-personalized ads are delivered instead.
- On Android, you can reset or delete your advertising ID and opt out of ad personalization in your device settings.
- For users in the EEA, the UK, and Switzerland, a consent management screen is shown on first launch, and personalized advertising is controlled according to your choice. You can change that choice at any time from "Ads & Privacy" in the My page.
- If you purchase the Pro version described below, no ads are shown and no information is collected for ad delivery.
Google Privacy Policy: https://policies.google.com/privacy
How Google uses data in advertising: https://policies.google.com/technologies/partner-sites
(2) Apple App Store / Google Play (in-app purchase)
The purchase of the "Pro version" (no ads, unlimited hints, all board themes) is processed through the billing platform provided by Apple Inc. or Google LLC. Payment information such as credit card numbers is never provided to us and we never hold it. All we refer to is whether a purchase exists.
(3) Retrieval of app configuration
On launch, the App communicates with our server (https://api.yomoestudio.com) to retrieve configuration such as the latest app version. This communication sends none of your play data and nothing that identifies you. By the nature of network communication, your IP address and the time of the request are recorded in the server access log; we use these only to prevent unauthorized access and to respond to incidents.
(4) Store review feature
Review prompts use the standard features provided by Apple and Google. Review content is sent to the respective store, and we cannot link a review to an individual user.
6. Provision to third parties
Except as described in the preceding section, we do not provide your information to third parties. This does not apply where disclosure is required by law.
7. Deleting data
Uninstalling the App deletes all data from your device, including play state, results, and settings. You can also erase your results from the "Reset statistics" feature inside the App. Because we do not hold your play data, there is no need to request deletion from us.
8. Your rights (GDPR / CCPA and similar)
Your play data exists only on your device and we do not hold it. The rights of access, rectification, erasure, and portability can therefore be exercised by you directly, through the App's reset and backup export features. We do not sell your personal information. Regarding the exercise of rights concerning data handled by advertising providers, please refer to the links in 5.(1) above.
9. Children
The App is not directed to children under 13. Minors should use the App with the consent and guidance of a parent or guardian.
10. Security
Because play data is stored on your device, its security depends on the security of the device itself (screen lock, OS updates, and so on). Please manage your device appropriately.
11. Language of this policy
The Japanese version of this policy is the authoritative text. We may provide translations into English and other languages for your convenience, but these are provided for reference only. In the event of any discrepancy or difference in interpretation between the Japanese version and a translation, the Japanese version prevails.
12. Changes to this policy
We may change this policy as necessary. If we make a material change, we will give notice within the App or through the app store. If you continue to use the App after a change, you are deemed to have agreed to the changed policy.
13. Contact
For inquiries about this policy, please contact us at:
Yomoe Studio
contact@yomoestudio.com