Terms of Service

Last updated: May 19, 2026

These Terms of Service ("Terms") govern your access to and use of the Mnemosyne application, websites, and related services (collectively, the "Service"), operated by YHLab ("we", "us", "our"). By creating an account or using the Service, you agree to these Terms.

1. Eligibility

You must be at least 14 years old to use the Service. If you are under the age of majority in your jurisdiction, you must have permission from a parent or legal guardian. By using the Service, you represent that you meet these requirements.

2. Your account

You are responsible for maintaining the confidentiality of your account credentials and for all activity that occurs under your account. Notify us immediately at yhlab.team@gmail.com if you suspect unauthorized use. We may suspend or terminate accounts that violate these Terms.

3. The Service

Mnemosyne is a learning tool that combines user-created and AI-generated study cards with a spaced-repetition system. The Service includes optional AI features (card generation, conversational assistance, long-term memory) powered by third-party large language models. AI output may be inaccurate, incomplete, or unsuitable for any specific purpose — you are responsible for verifying it before relying on it.

4. Subscriptions and payment

4.1 Plans

The Service offers a free tier and paid subscription tiers (currently Pro and Patron). Current pricing is shown on our Pricing page. We may change pricing prospectively with reasonable notice; changes will not affect your current billing period.

4.2 Web billing (Paddle)

Web subscriptions are sold by Paddle.com Market Limited ("Paddle"), our Merchant of Record. Paddle is responsible for processing payment, collecting applicable sales tax / VAT, issuing invoices, and handling billing inquiries. By subscribing on the web, you also agree to Paddle's Checkout Buyer Terms.

4.3 Mobile billing (App Store / Google Play)

Mobile subscriptions are sold and billed by Apple or Google according to the terms of their respective stores. Refunds, cancellations, and renewal management for mobile subscriptions are governed by the relevant store's policies.

4.4 Auto-renewal

Subscriptions automatically renew at the end of each billing period at the then-current price until canceled. You can cancel at any time; access continues until the end of the period already paid for.

4.5 Refunds

Refund eligibility and procedures are described in our Refund Policy.

5. Your content

You retain ownership of all study materials, notes, sources, and other content you upload or create in the Service ("User Content"). You grant us a worldwide, non-exclusive, royalty-free license to host, store, transmit, display, and process User Content solely as necessary to operate and improve the Service for you. We do not use your User Content to train foundational AI models. You are responsible for ensuring you have the rights to upload your User Content and that it does not infringe any third party's rights.

6. Acceptable use

You agree not to:

Upload content that is unlawful, infringing, defamatory, or that violates another person's privacy or intellectual property rights;
Use the Service to generate or distribute spam, malware, or fraudulent content;
Reverse-engineer, decompile, or attempt to extract source code of the Service, except as permitted by law;
Resell, sublicense, or commercially exploit the Service without our prior written consent;
Use automated means to access the Service in a way that exceeds normal human use or overloads our infrastructure;
Circumvent, disable, or interfere with security-related features of the Service.

7. Intellectual property

The Service, including its software, branding, character designs, illustrations, and all related intellectual property, is owned by us or our licensors and is protected by copyright, trademark, and other laws. These Terms do not grant you any rights to our trademarks, logos, or character assets.

8. Third-party services

The Service integrates with third-party providers including Google (Firebase, Gemini), RevenueCat, Paddle, and others. Your use of features that depend on these providers is also subject to their terms. We are not responsible for the acts or omissions of third-party providers.

9. Disclaimers

The Service is provided "as is" and "as available" without warranties of any kind, whether express or implied, including warranties of merchantability, fitness for a particular purpose, or non-infringement. We do not warrant that the Service will be uninterrupted, error-free, or that AI-generated content will be accurate or suitable for any specific purpose.

10. Limitation of liability

To the maximum extent permitted by law, in no event will we be liable for any indirect, incidental, special, consequential, or punitive damages, or any loss of profits, revenue, data, or goodwill arising out of your use of the Service. Our total aggregate liability for any claim arising out of or relating to the Service is limited to the greater of (a) the amount you paid us in the twelve months preceding the claim, or (b) USD 50.

11. Termination

You may stop using the Service at any time and delete your account from in-app settings (Menu → Account → Delete account). Account deletion is immediate and irreversible: your account, study content, conversations, journal entries, crystals, and Aether balance are removed from our active systems as soon as the request is processed, with no recovery window. Information that we are legally required to retain (such as payment and transaction records under Korean tax and e-commerce law) is preserved only for the period required by that law. We may suspend or terminate your access if you materially breach these Terms, or if we are required to do so by law. On termination, your right to use the Service ends immediately; sections that by their nature should survive (including ownership, disclaimers, limitation of liability, and dispute resolution) will survive.

12. Changes to the Terms

We may update these Terms from time to time. Material changes will be notified through the Service or by email at least 14 days before they take effect. Your continued use of the Service after changes take effect constitutes acceptance of the updated Terms.

13. Governing law

These Terms are governed by the laws of the Republic of Korea, without regard to its conflict-of-law principles. Where you are a consumer, you also benefit from any mandatory consumer-protection provisions of the country in which you reside, which apply in addition to these Terms.

14. Contact

For questions about these Terms, contact us at yhlab.team@gmail.com or by mail at YHLab, 20, Heungdeok 1-ro, Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea.