Lemmi Terms of Use

Effective date: 2026-10-07

These terms apply to the Lemmi mobile apps and related services ("Lemmi"), provided by Andrii Voitenko, a private individual ("I", "we"). By using Lemmi you agree to these terms. How we handle personal data is described in the Privacy Policy.

1. The service

Lemmi helps you learn English vocabulary with exercises and spaced repetition. The core of Lemmi is free of charge and has no ads: all 5000 words, the level test, every exercise and the spaced-repetition schedule. Lemmi Pro is an optional paid subscription that adds features on top (section 2).

2. Lemmi Pro

• What it includes. Lemmi Pro currently adds word collections beyond the 5000 words, your own practice modes and detailed statistics with an export. What Pro includes is described in the app before you buy. We may add, change or replace Pro features over time; we will not take away the free core described in section 1.
• Purchase and billing. Pro is sold as an auto-renewing subscription (monthly or yearly) through the App Store or Google Play. The store charges you, under its own terms, and shows the price and the period before you confirm.
• Free trial. If a plan offers a free trial, the subscription starts with it and the first payment is taken when the trial ends, unless you cancel before then.
• Renewal and cancellation. The subscription renews automatically at the end of each period at the same price unless you cancel at least 24 hours before the period ends. You cancel or change it in your App Store or Google Play account settings (in Lemmi: Settings → Lemmi Pro → Manage subscription). After cancelling, Pro stays on until the end of the paid period.
• Refunds. Refunds are handled by the store under its rules (Apple: reportaproblem.apple.com; Google Play: the order in your Google account). Where the law of your country gives you a right to withdraw from the purchase, you exercise it with the store.
• Price changes. If the price of a subscription changes, the store informs you in advance and, where required, asks for your consent before the new price applies.
• Your account and devices. Pro bought while signed in works on all your devices and on the web with the same account. Bought without an account, it stays on that device until you sign in, and can be restored there with Restore purchases. Deleting your Lemmi account does not cancel a running subscription: cancel it in the store.
• Pro granted by us. We may give Pro for a limited time, for example to people who supported Lemmi with a donation. Such Pro ends on the date we tell you and does not renew.

3. Who can use Lemmi

You must be at least 13 years old, or 16 in the EU/EEA. If you are below the age of majority where you live, a parent or guardian should agree to these terms with you.

4. Your account

• You can use Lemmi without an account. An account lets you keep your progress and sync it between devices.
• Keep your password secure and do not share your account. You are responsible for what happens in your account.
• You can delete your account at any time in Settings → Privacy → Delete account.

5. Acceptable use

Do not:

• break the law using Lemmi;
• try to access other people's data or systems you are not allowed to access;
• interfere with the service, for example by automated mass requests, scraping the word database, or probing for vulnerabilities without permission;
• misuse the error-report feature (spam, abuse, personal data of others).

If you find a security issue, please report it responsibly to privacy@getlemmi.app.

We may suspend or delete accounts that seriously or repeatedly break these rules.

6. Content and licences

• The word list, definitions, translations, example sentences, exercises and app design are provided for your personal learning.

• Parts of the word list are based on openly licensed datasets:

  • NGSL / NAWL, Octanove Vocabulary Profile and FrequencyWords (CC BY-SA 4.0);
  • CEFR-J Wordlist (used with citation).

  Portions derived from CC BY-SA material are available under the same licence.

• Audio is generated with openly licensed text-to-speech models.

• The full list of sources and licences is in the app under Settings → About.

We work hard to make the content accurate, but it may contain mistakes. Please report them from the app. Lemmi is a learning aid and does not guarantee any exam result or level of proficiency.

7. Error reports you send

When you report a problem with a word, you allow us to use the report to fix and improve the content. Please do not include personal information in the comment.

8. Availability and changes

We aim to keep Lemmi running reliably, but it is provided by an individual developer and may occasionally be unavailable, change, or, in the worst case, be discontinued. If Lemmi is going to shut down, we will announce it in advance, give you a way to export your data and stop renewing Lemmi Pro subscriptions.

9. Disclaimer and liability

Lemmi is provided "as is", without warranties of any kind, to the extent permitted by law.

To the extent permitted by law, we are not liable for indirect or consequential damages, or for loss of data or learning progress. Nothing in these terms limits liability that cannot be limited by law, such as liability for intent or gross negligence, or your mandatory rights as a consumer under the law of your country of residence.

10. Changes to these terms

We may update these terms. For significant changes we will notify you in the app before they take effect. If you do not agree, you can stop using Lemmi, cancel Lemmi Pro in the store and delete your account.

11. Governing law

These terms are governed by the law of Ukraine. If you are a consumer, you also keep the protection of the mandatory provisions of the law of your country of residence, and you may bring claims in the courts there.

12. Contact

Andrii Voitenko · support@getlemmi.app