Terms of Use

1. Acceptance of These Terms

Sand Nihongo is a mobile application published by Sandpia ("we," "our," or "us") that helps you learn Japanese for the JLPT (N5–N1). These Terms of Use ("Terms") form an agreement between you and us that governs your use of the app. By downloading, installing, or using Sand Nihongo, you agree to these Terms. If you do not agree, please do not use the app.

Your use of the app is also subject to the terms and policies of the store you downloaded it from (the Apple App Store or Google Play). Where those store terms differ from these Terms, the store terms apply to your relationship with that store.

2. License to Use the App

We grant you a personal, limited, non-exclusive, non-transferable, and revocable license to download and use Sand Nihongo on any device that you own or control, solely for your own personal, non-commercial learning. This license is granted in accordance with the rules of the app store you downloaded the app from.

3. Eligibility

Sand Nihongo is intended for a general audience and is not directed to children under 13. If you are a minor in your country, you should use the app only with the involvement of a parent or guardian.

4. Educational Content — No Guarantee of Results

Sand Nihongo provides study material for the JLPT, including kanji writing practice, vocabulary, hiragana and katakana, and reading and listening content. This material is provided for general educational purposes only.

We do not guarantee any particular learning outcome and are not affiliated with, endorsed by, or connected to the Japan Foundation, Japan Educational Exchanges and Services, or any official JLPT organization. Using the app does not guarantee that you will pass the JLPT or reach any specific level. While we work to keep the content accurate, we do not warrant that it is error-free, complete, or up to date.

5. AI-Generated Content

Portions of the content in Sand Nihongo — including, without limitation, images, illustrations, graphics, and audio such as voice or pronunciation recordings — may be generated, produced, or assisted using generative artificial intelligence (AI) tools and automated systems. We make no representation or warranty that any such content was created, drawn, recorded, reviewed, or verified by a human, and we do not guarantee that it originates from, reflects, or corresponds to any real person, voice, native speaker, place, or object.

AI-generated content is provided strictly on an "as is" and "as available" basis and may contain errors, inaccuracies, artifacts, unnatural elements, or output that does not accurately reflect real-world facts, correct Japanese usage, or native-standard pronunciation. To the maximum extent permitted by applicable law, we disclaim all liability for any reliance on, or use of, AI-generated content, and you agree that you use it at your own risk. You should not treat AI-generated audio as an authoritative standard for pronunciation, or AI-generated images or text as factually accurate.

By using the app, you acknowledge and accept that some content is or may be AI-generated, that it is not represented to be human-made, and that this Section is in addition to, and does not limit, the Disclaimer of Warranties and Limitation of Liability set out below.

6. Acceptable Use

When using Sand Nihongo, you must NOT:

• copy, modify, distribute, sell, or lease any part of the app or its content;
• reverse engineer, decompile, or attempt to extract the source code of the app, except to the extent this restriction is prohibited by applicable law;
• use the app in any unlawful way or for any unlawful purpose;
• interfere with or disrupt the app, our servers, or the networks used to provide the app; or
• attempt to bypass advertisements, in-app purchase mechanisms, or any access or security controls in the app.

7. Intellectual Property

The app and its content — including text, learning material, audio, graphics, logos, and software — are owned by us or our licensors and are protected by intellectual property laws. Except for the limited license described above, these Terms do not grant you any rights in the app or its content.

8. In-App Purchases and Subscriptions

Sand Nihongo offers two optional in-app purchases. Both unlock the same benefits: studying without the periodic ad breaks, and downloading the voice files for offline study.

• Lifetime purchase — a one-time payment with no recurring charge. It does not renew and does not expire on its own. Your access continues for as long as we make the app and the relevant feature available (see Section 14).
• Monthly subscription — an auto-renewable subscription with a term of one (1) month.

You only need one of the two. Buying the lifetime purchase does not cancel an active monthly subscription; if you have both, cancel the subscription in your store account settings to stop further charges.

All purchases are processed by the Apple App Store or Google Play, not by us. We do not receive or store your payment card details.

Auto-renewal. The monthly subscription renews automatically unless it is canceled at least 24 hours before the end of the current period. Payment is charged to your Apple ID or Google account upon confirmation of purchase, and again at or shortly before the start of each renewal period at the then-current price, in accordance with the store's own billing rules. The price and billing period are shown before you buy.

Managing and canceling. You can manage, pause (where the store offers it), or cancel your subscription at any time in your App Store account settings (Settings › your name › Subscriptions) or your Google Play account settings. Canceling stops future renewals, and your access continues until the end of the period you have already paid for. Deleting the app does not cancel your subscription.

Keeping your subscription active. For the monthly subscription, the app re-checks with the store from time to time. If it cannot reach the store for an extended period — for example if your device stays offline for several days — subscription-based access may pause until the check succeeds. The lifetime purchase is not affected by this. The app supports the purchase restore procedure provided by each store: signing in with the same store account (the same Apple ID, or the same Google account) and using "Restore purchases" in the app asks the App Store or Google Play to restore your lifetime purchase or active subscription — for example on a new device or after reinstalling. The restore itself is carried out by the store, and a purchase made on one store cannot be restored on the other.

Price changes. Any change to the subscription price is handled by the store under its own rules, including its own notice and consent procedures. You can cancel in your store account settings before a change takes effect.

Refunds. Prices, billing, and refunds are handled by the store under its own terms and refund policy, and we generally cannot issue refunds directly. If a purchase is refunded, reversed, or charged back, we may remove the access it granted, so ads may reappear and paid features may be locked again. None of this affects any statutory right of withdrawal, cancellation, or refund you may have under the consumer law of your country. If a purchase you have made is not applied correctly, please contact us and we will try to help.

9. Advertisements

Unless you have purchased an ad-free option, Sand Nihongo displays advertisements through Google AdMob and its mediation partners, such as Meta Audience Network. Ads are provided by third parties, and we are not responsible for the content of any advertisement or for any products or services promoted in them. How advertising data is handled is described in our Privacy Policy.

10. Third-Party Services

Sand Nihongo may use third-party services, including Google AdMob and its mediation partners (which may include Meta Audience Network) for advertising, and — where you choose to enable them — Firebase Analytics and Firebase Crashlytics. Your use of the app may be subject to these providers' own terms and privacy policies. We are not responsible for the practices of these third parties.

11. Privacy

Your use of Sand Nihongo is also governed by our Privacy Policy, which explains what data the app processes and how it is handled. By using the app, you acknowledge that you have read the Privacy Policy.

12. Disclaimer of Warranties

Sand Nihongo is provided "as is" and "as available," without warranties of any kind, whether express or implied, including implied warranties of merchantability, fitness for a particular purpose, and non-infringement. We do not warrant that the app will be uninterrupted, secure, or error-free, that defects will be corrected, or that the app or the servers that provide it are free of harmful components. Some jurisdictions do not allow the exclusion of certain warranties, so some of the above exclusions may not apply to you.

13. Limitation of Liability

To the maximum extent permitted by applicable law, we will not be liable for any indirect, incidental, special, consequential, or punitive damages, or for any loss of data, profits, or goodwill, arising out of or related to your use of (or inability to use) Sand Nihongo. Nothing in these Terms limits liability that cannot be limited under applicable law, including your mandatory rights as a consumer.

14. Changes to the App and These Terms

We may update, change, or discontinue the app or any of its features at any time. We may also update these Terms from time to time. When we do, we will post the updated Terms on this page and change the "Last updated" date. Your continued use of the app after changes take effect means you accept the updated Terms.

15. Termination

You may stop using Sand Nihongo at any time by uninstalling it. We may suspend or end your access to the app if you materially breach these Terms or use the app in a way that could cause harm or legal liability. Sections that by their nature should survive termination — such as intellectual property, disclaimers, and limitation of liability — will continue to apply.

16. Governing Law

These Terms are governed by the laws of the Republic of Korea, without regard to conflict-of-law rules. Regardless of that, if you are a consumer, you keep the benefit of any mandatory consumer-protection rules of the country where you live, and nothing in these Terms takes those rights away.

17. Contact Us

If you have any questions about these Terms, please contact us at:

[email protected]

18. Additional Terms for the Apple App Store

This Section applies only if you obtained Sand Nihongo from the Apple App Store. It supplements the license agreement that applies to your download from the App Store.

Acknowledgement. These Terms are concluded between you and Sandpia only, and not with Apple Inc. ("Apple"). Sandpia, not Apple, is solely responsible for Sand Nihongo and its content.

Scope of license. For the App Store version, the license granted in Section 2 is a non-transferable license to use Sand Nihongo on any Apple-branded products that you own or control, and as permitted by the Usage Rules set out in the Apple Media Services Terms and Conditions.

Maintenance and support. Sandpia is solely responsible for any maintenance and support for the app. Apple has no obligation whatsoever to furnish any maintenance or support services.

Warranty. Sandpia is solely responsible for any product warranties, whether express or implied by law, to the extent not effectively disclaimed. If the app fails to conform to any applicable warranty, you may notify Apple, and Apple will refund the purchase price (if any) of the app to you. To the maximum extent permitted by applicable law, Apple will have no other warranty obligation whatsoever with respect to the app.

Product claims. Sandpia, not Apple, is responsible for addressing any claims by you or any third party relating to the app or your possession and use of it, including product liability claims, any claim that the app fails to conform to any applicable legal or regulatory requirement, and claims arising under consumer protection, privacy, or similar legislation.

Intellectual property. In the event of any third-party claim that the app or your possession and use of it infringes that third party's intellectual property rights, Sandpia, not Apple, will be solely responsible for the investigation, defense, settlement, and discharge of any such claim.

Legal compliance. You represent and warrant that you are not located in a country that is subject to a U.S. Government embargo or that has been designated by the U.S. Government as a "terrorist supporting" country, and that you are not listed on any U.S. Government list of prohibited or restricted parties.

Third-party terms. You must comply with any applicable third-party terms of agreement when using Sand Nihongo.

Third-party beneficiary. You and Sandpia acknowledge and agree that Apple and Apple's subsidiaries are third-party beneficiaries of these Terms, and that upon your acceptance of these Terms, Apple will have the right (and will be deemed to have accepted the right) to enforce these Terms against you as a third-party beneficiary.