Last updated: July 1, 2026

Terms of Service

Please read these Terms of Service ("Terms") carefully before using Keystone (the "App"). By downloading or using the App, you agree to be bound by these Terms.

1. Acceptance of Terms

By accessing or using Keystone, you confirm that you are at least 13 years of age and agree to these Terms. If you do not agree, please do not use the App.

2. License

Keystone grants you a limited, non-exclusive, non-transferable, revocable license to use the App on Apple-branded devices you own or control, strictly in accordance with these Terms and Apple's App Store Terms of Service.

You may not:

3. Subscriptions and In-App Purchases

Keystone offers optional Pro features available through a subscription or one-time purchase via the Mac App Store. All billing is handled by Apple. Prices, billing cycles, and cancellation policies are governed by Apple's terms.

4. Free Tier Limitations

The free version of Keystone includes access to core features with certain limits (for example, a cap on the number of profiles and linked projects). Pro features require an active subscription or purchase. Limits apply only to creating new items beyond the cap — your existing data is never deleted if a subscription lapses. We reserve the right to adjust free tier limits at any time.

5. Your Content and Files

Keystone reads and writes rules and skills files within the folders you explicitly link, and stores your profiles locally and, if enabled, in your private iCloud account. You retain full ownership of your content. We do not claim any rights to the rules, skills, or project files you create or manage using the App. You are responsible for maintaining your own backups; while Keystone is designed to be non-destructive, you use the App at your own risk.

6. Intellectual Property

All content, design, code, and assets within the App are owned by or licensed to Keystone. Nothing in these Terms transfers ownership of any intellectual property to you. The Keystone name, logo, and associated marks may not be used without prior written permission.

7. Disclaimer of Warranties

The App is provided "as is" and "as available" without warranties of any kind, either express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, or non-infringement. We do not warrant that the App will be error-free or uninterrupted, or that it will never modify a file in an unintended way.

8. Limitation of Liability

To the fullest extent permitted by law, Keystone shall not be liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of or inability to use the App, including any loss of or damage to files, even if advised of the possibility of such damages. Our total liability shall not exceed the amount you paid for the App in the twelve months preceding the claim.

9. Termination

We reserve the right to suspend or terminate your access to the App at our sole discretion, without notice, if you violate these Terms. Upon termination, all licenses granted to you under these Terms will immediately cease.

10. Governing Law

These Terms are governed by and construed in accordance with applicable law. Any disputes arising under these Terms shall be resolved in the appropriate courts of competent jurisdiction.

11. Changes to These Terms

We may update these Terms from time to time. Continued use of the App after any changes constitutes your acceptance of the new Terms. We will update the "Last updated" date at the top of this page when changes are made.

12. Apple App Store Additional Terms

As Keystone is distributed via the Mac App Store, Apple's Standard Licensed Application End User License Agreement (Standard EULA) applies, together with applicable App Store terms. In case of conflict between these Terms and Apple's terms, Apple's terms govern with respect to App Store usage.

13. Contact

For questions about these Terms, please contact us at:
support@keystoneforai.com