Terms of Service

Last Updated: January 2026

            Modern Master Key is completely free. There are no subscriptions, no in-app purchases, and no hidden fees.
        

1. Acceptance of Terms

By downloading, installing, or using the Modern Master Key iOS application ("the App"), you agree to be bound by these Terms of Service ("Terms"). If you do not agree to these Terms, please do not use the App.

2. Description of Service

Modern Master Key provides free access to Charles F. Haanel's "The Master Key System," a 24-part personal development course originally published in 1912. The App includes:

The complete, unabridged text of all 24 parts
Introduction and supplementary materials
Reading progress tracking
Customization features (dark mode, text size)
Daily inspirational quotes

3. Free Access

The core content of Modern Master Key will always remain free. We may introduce optional premium features in the future, but:

All 24 parts of The Master Key System will always be accessible at no cost
We will never place existing free content behind a paywall
Premium features, if introduced, will be clearly marked as optional enhancements

4. Intellectual Property

Public Domain Content: The Master Key System by Charles F. Haanel is in the public domain in the United States.

Trademarks: "Modern Master Key" and associated logos are trademarks of Hartshorne Works LLC.

5. Permitted Use

You may:

Use the App for personal, non-commercial purposes
Read and study the content
Share quotes or passages with proper attribution
Recommend the App to others

6. Prohibited Use

You may not:

Copy, redistribute, or republish the App or its compiled content
Reverse engineer, decompile, or disassemble the App
Remove or alter any copyright notices or trademarks
Use the App for any unlawful purpose
Attempt to access or interfere with the App's systems or infrastructure

7. User-Generated Content

The App currently does not support user-generated content (reviews, comments, notes sharing). Any future features allowing user content will be governed by additional terms.

8. Privacy

Your use of the App is also governed by our Privacy Policy. In summary:

We collect no personal information
All data is stored locally on your device
We do not track, sell, or share your data

9. 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:

Fitness for a particular purpose
Accuracy or completeness of content
Uninterrupted or error-free operation

Educational Content Only: The Master Key System contains philosophical and self-improvement principles. It is not a substitute for professional advice (medical, legal, financial, or psychological). Use of the principles is at your own discretion and risk.

10. Limitation of Liability

To the maximum extent permitted by law, Hartshorne Works LLC and its affiliates shall not be liable for any:

Direct, indirect, incidental, or consequential damages
Loss of profits, data, or use
Personal injury or property damage

arising from your use or inability to use the App, even if we have been advised of the possibility of such damages.

11. Changes to the App

We reserve the right to:

Modify, update, or discontinue features at any time
Add optional premium features in the future
Change these Terms with notice to users

We will notify users of significant changes through the App or our website.

12. Third-Party Links

The App may contain links to third-party websites or resources (such as our social media). We are not responsible for the content, privacy practices, or terms of these third parties.

13. Termination

You may stop using the App at any time by deleting it from your device. We reserve the right to terminate or restrict access to the App for violations of these Terms.

14. Children's Privacy

The App is suitable for all ages. We do not knowingly collect personal information from anyone, including children under 13, as we collect no personal information at all.

15. Governing Law

These Terms are governed by the laws of the State of New Jersey, United States, without regard to conflict of law principles. Any disputes shall be resolved in the courts of New Jersey.

16. Severability

If any provision of these Terms is found to be invalid or unenforceable, the remaining provisions will continue in full force and effect.

17. Entire Agreement

These Terms, together with our Privacy Policy, constitute the entire agreement between you and Hartshorne Works LLC regarding the use of Modern Master Key.

18. Contact Information

If you have questions about these Terms of Service, please contact us:

Email: support@modernmasterkey.com

Website: www.modernmasterkey.com

Business Entity: Hartshorne Works LLC

19. Acknowledgment

By using Modern Master Key, you acknowledge that you have read, understood, and agree to be bound by these Terms of Service.