Terms and Conditions of Use

1. Who can use Lemma

To use the Service you must be at least 18 years old and have the legal capacity to enter into a binding contract. By using Lemma, you represent that you meet these requirements.

The Service is available globally to anyone with internet access, except where prohibited by law. You are responsible for complying with the laws applicable in your country.

2. Your account

Registration is done solely through your Google account. You are responsible for keeping your account confidential and for all activity that occurs under it.

You must provide truthful information and keep it up to date. An account belongs to a single person; you must not share your account or allow third parties to use it.

Notify us immediately at hola@trylemma.io if you detect any unauthorized use of your account.

3. The Service

Lemma is an adaptive platform for language learning. Its core features include flashcard decks with spaced repetition, quick practice (readings and audio), novels, a conversation companion, and an assistant (the “Coach”), among others. Much of the content is generated automatically and personally through artificial intelligence.

We may modify, add, or discontinue features of the Service at any time to improve it or for technical, legal, or business reasons.

4. Content generated by artificial intelligence

The Service uses artificial intelligence to generate explanations, stories, examples, answers, and other materials. This content may contain errors, inaccuracies, or incomplete or outdated information.

Lemma's content is for educational and language-practice purposes. It does not constitute professional, medical, legal, financial, or any other kind of advice. You should use your own judgment and verify information when it matters.

5. Subscription, trial, and payments

Free trial. When you sign up, you receive a Lemma Pro trial period with access to all generative features. When the trial ends, your account continues for free on its Standard version (with limited features), unless you subscribe to Lemma Pro.

Subscription. Lemma Pro is a recurring paid subscription. The applicable price is the one shown at the time of purchase. The subscription renews automatically at the end of each period until you cancel it.

Payment processing. Payments are processed through Stripe, which handles billing and, where applicable, currency conversion. We do not store your full card details; these are handled by Stripe under its own terms and policies.

Taxes. Prices may not include taxes. You are responsible for any applicable taxes that we are not required to collect.

6. Cancellation and refunds

You may cancel your subscription at any time. Cancellation takes effect at the end of the current billing period; you will keep access to Lemma Pro until that date, and no further charges will be made.

Unless applicable law requires otherwise, payments for periods already charged are non-refundable, even if you cancel before the period ends.

Consumers in the European Union / United Kingdom. If you are a consumer in these regions, you may have the right to withdraw from the contract within 14 days of entering into it. However, by starting to use the digital Service within that period, you request its immediate provision and acknowledge that you lose the right of withdrawal once the Service has been fully performed.

7. Acceptable use

By using Lemma, you agree not to:

• Use the Service for any unlawful or unauthorized purpose, or violate any applicable law.
• Enter, generate, or distribute content that is illegal, fraudulent, defamatory, that infringes third-party rights, or that is abusive, harassing, or harmful.
• Attempt to use the AI to generate prohibited or dangerous content, or content that violates the terms of our technology providers.
• Share sensitive personal information (your own or others') through the Coach, the companions, or other features (see section 9).
• Interfere with the Service, circumvent security measures, access it by unauthorized means, or scrape, reverse-engineer, or copy the software.
• Resell, sublicense, commercially exploit, or redistribute the Service or its content without our written authorization.
• Impersonate another person or share your account with third parties.

8. Your content and license

You retain ownership of the information and materials you enter into the Service (“Your Content”), such as messages, decks, or preferences.

You grant us a worldwide, non-exclusive, royalty-free license to host, process, reproduce, and adapt Your Content for the sole purpose of operating, personalizing, and improving the Service, including its transmission to the artificial intelligence and infrastructure providers that make the Service possible.

You acknowledge that what you write or say to the Coach, the companions, or other features is processed automatically and shared with those providers. Treat that information as if you were sharing it freely, and do not include sensitive data.

9. Sensitive information

Lemma is not designed to receive sensitive personal information. Do not share through the Service any health, financial, or biometric data, credentials, official identifiers, or any other information whose disclosure could harm you or others. You are responsible for the information you choose to enter.

10. Intellectual property

The Service, including the software, design, the “Lemma” brand, logos, and the elements that compose it, is owned by Lemma or its licensors and is protected by intellectual property laws.

We grant you a limited, personal, non-transferable, and revocable license to use the content generated for you (such as stories, novels, or explanations) solely for personal, non-commercial learning purposes. You acquire no other rights over the Service or its content.

11. Privacy

Our processing of your personal data is governed by our Privacy Notice, which forms part of these Terms. By using the Service, you accept that processing, including the collection of data derived from your interaction with the app to personalize your experience and measure your language level.

12. Suspension and termination

We reserve the right to suspend or terminate your account and your access to the Service, at any time and at our discretion, if we believe you have breached these Terms, that your use poses a legal or security risk, or where the law requires it.

You may stop using the Service and request the deletion of your account at any time by writing to us at hola@trylemma.io.

13. Disclaimer of warranties

The Service is provided “as is” and “as available,” without warranties of any kind, express or implied. We do not warrant that the Service will be uninterrupted, error-free, or secure, that it will produce specific learning outcomes, or that AI-generated content will be accurate or complete.

14. Limitation of liability

To the maximum extent permitted by law, Lemma and its operators will not be liable for indirect, incidental, special, consequential, or punitive damages, or for loss of data, profits, or opportunities, arising from your use of or inability to use the Service.

To the extent permitted by law, our total aggregate liability relating to the Service will not exceed the amount you have paid us in the twelve (12) months prior to the event giving rise to the claim. Nothing in these Terms limits liabilities that cannot be excluded by law, nor the mandatory rights you may have as a consumer.

15. Indemnification

You agree to hold Lemma and its operators harmless from any claim, loss, or expense (including reasonable attorneys' fees) arising from your use of the Service, from Your Content, or from your breach of these Terms or of the law.

16. Changes to these Terms

We may update these Terms to reflect changes in the Service or in the law. We will post the current version with its update date and, when changes are significant, we will endeavor to notify you by reasonable means. Continued use of the Service after they take effect constitutes your acceptance.

17. Governing law and jurisdiction

These Terms are governed by the laws of the United Mexican States. Any dispute will be submitted to the competent courts in Mexico, without prejudice to the mandatory consumer-protection rights granted to you by the law of your country of residence.

18. General provisions

If any provision of these Terms is held invalid, the remaining provisions will remain in effect. Our failure to exercise a right does not constitute a waiver of it. These Terms, together with the Privacy Notice, constitute the entire agreement between you and Lemma regarding the Service.

19. Contact

For any questions about these Terms, write to us at hola@trylemma.io.