Terms of Use

Last updated November 3, 2026

These Terms of Use ("Terms") govern your use of the Slate Chess app for iPhone, iPad, Mac and Apple TV (the "App"), the Slate chess engine, and the website at slatechess.com (together, the "Service"), provided by Turtle Leap LLC ("we", "us"). By downloading or using the Service you agree to these Terms. If you do not agree, do not use it.

1. Who can use it

You must be at least 13 years old. If you are under the age of majority where you live, a parent or guardian must agree to these Terms on your behalf. The App does not require an account for its core features.

2. Licence

We grant you a personal, non-exclusive, non-transferable, revocable licence to install and use the App on Apple devices you own or control, as permitted by the Apple Media Services Terms and Conditions and the Usage Rules in them. All rights not expressly granted are reserved. You may not copy, modify, reverse engineer, decompile or extract the source code of the App or the Slate engine, or sell, rent or sublicense them, except where applicable law or an open-source licence that covers a component expressly allows it.

3. Fair play

Slate Chess is a learning tool. Do not use the App, the engine or any output of either to cheat in rated games, tournaments, competitions or any other setting where outside assistance is not allowed, on any platform. Do not use the Service to harass others, to break the law, or to interfere with or overload it.

4. Coaching and ratings are estimates

Move grades, evaluations, explanations, opponent levels and any ratings shown (including approximate level ratings and the engine's rating, which is our own unofficial measurement) are estimates intended to help you learn. They are not official ratings and are not guarantees of results or improvement.

5. Subscriptions and purchases

Slate Chess is free to download. Premium, which unlocks Game Review with the coach, the mistake deck and weak-spot drills, is a subscription (Monthly, Yearly or Family) sold, billed and managed by Apple through your Apple Account; every install starts with three free games, and paid plans start with a 7-day free trial. The Family plan covers up to six people in an Apple Family Sharing group. Prices, renewal and cancellation are governed by Apple's terms; you can manage or cancel a subscription at any time in your Apple Account settings. We do not receive your payment details. Refund requests are handled by Apple.

6. Our content and open source

The App, the Slate engine, the Slate Chess name and logos, and our content belong to Turtle Leap LLC and its licensors and are protected by intellectual-property laws. Some components are open source and are provided under their own licences, which apply to those components instead of these Terms; see Acknowledgements. Your own games stay yours.

7. Beta software

Pre-release builds (for example through TestFlight) are provided "as is", may contain errors, may change or stop working, and are subject to Apple's TestFlight terms. Feedback you send us may be used by us to improve the Service without obligation to you.

8. Third-party services

The Service may link to or work with services we do not control (for example Lichess or Apple). Their terms and privacy practices apply to your use of them, and we are not responsible for them. Slate Chess is not affiliated with Lichess.

9. Disclaimer of warranties

To the fullest extent permitted by law, the Service is provided "as is" and "as available", without warranties of any kind, express or implied, including merchantability, fitness for a particular purpose, accuracy and non-infringement. We do not warrant that the Service will be uninterrupted or error-free.

10. Limitation of liability

To the fullest extent permitted by law, Turtle Leap LLC will not be liable for any indirect, incidental, special, consequential or punitive damages, or for lost profits, data or goodwill, arising from your use of the Service. Our total liability for any claim relating to the Service is limited to the greater of the amount you paid us for the Service in the 12 months before the claim and US$50. Some jurisdictions do not allow certain limits, so parts of this section may not apply to you.

11. Apple-specific terms

These Terms are between you and Turtle Leap LLC, not Apple. Turtle Leap LLC, not Apple, is solely responsible for the App and its content. You acknowledge that:

• Apple has no obligation to provide maintenance or support for the App.
• If the App fails to conform to an applicable warranty, you may notify Apple, which will refund the purchase price (if any); to the extent permitted by law, Apple has no other warranty obligation for the App, and any other claims, losses or costs for non-conformity are our responsibility.
• We, not Apple, are responsible for addressing any claims relating to the App or your use of it, including product liability, legal or regulatory compliance, and consumer-protection claims.
• If a third party claims the App infringes its intellectual-property rights, we, not Apple, are responsible for the investigation, defence, settlement and discharge of that claim.
• You represent that you are not located in a country subject to a US Government embargo or designated as a "terrorist supporting" country, and that you are not on any US Government list of prohibited or restricted parties.
• You must comply with applicable third-party terms (for example your wireless data agreement) when using the App.
• Apple and its subsidiaries are third-party beneficiaries of these Terms and, once you accept them, Apple may enforce them against you.

12. Changes and termination

We may update the Service and these Terms. If a change is material we will tell you, for example in the App or on this page, and the date above will change. Continuing to use the Service after a change means you accept it. We may suspend or end your access if you break these Terms. You may stop using the Service at any time by deleting the App.

13. Governing law

These Terms are governed by the laws of the State of Delaware, USA, without regard to conflict-of-law rules, and disputes will be resolved in the state and federal courts located in Delaware, except where your local consumer law gives you the right to bring claims elsewhere.

14. Contact

Questions about these Terms: support@slatechess.com.