Terms of Use
Last updated: April 2026
By downloading, installing, or using Kael ("the App"), you agree to be bound by these Terms of Use ("Terms"). If you do not agree, do not use the App. Kael is operated by Yuhua Wu ("we", "us", "our").
The Service
Kael is an AI-powered habit coaching app that helps you build and maintain daily habits. Features include habit tracking, mood logging, AI coaching chat, and subscription-based premium access.
We reserve the right to modify, suspend, or discontinue any part of the Service at any time with reasonable notice where possible.
Accounts
You must provide accurate information when creating an account. You are responsible for maintaining the security of your account credentials and for all activity under your account. You must be at least 13 years old (or the minimum age in your jurisdiction) to use Kael.
Subscriptions and payments
Kael offers a free tier and paid subscriptions. Paid subscriptions unlock additional features including expanded AI coaching.
- iOS subscriptions — billed through Apple App Store. A 7-day free trial is available for new subscribers. Subscriptions auto-renew monthly unless cancelled at least 24 hours before the renewal date. To cancel, go to Settings → [Your Name] → Subscriptions on your device.
- Web subscriptions — billed through Stripe. Cancellation and billing management are available at kaelvoice.com/settings.
Prices are shown in your local currency where available. Refunds for iOS purchases are handled by Apple; refund requests for web subscriptions should be sent to kael6688@proton.me.
AI features
AI coaching features are powered by OpenAI. When you enable AI coaching, your messages and habit data are sent to OpenAI for processing. By enabling AI coaching, you consent to this data transfer. You can disable AI coaching at any time in Settings.
AI responses are generated automatically and are not a substitute for professional medical, psychological, or nutritional advice. Do not rely on AI coaching for medical decisions.
User conduct
You agree not to:
- Use the App for any unlawful purpose
- Attempt to reverse-engineer, decompile, or otherwise access the App's source code
- Use automated means to access the App or its API without permission
- Submit content that is harmful, abusive, or violates the rights of others
- Misuse AI features to generate harmful content
Intellectual property
The App, including its design, code, branding, and content, is owned by us and protected by applicable intellectual property laws. You retain ownership of the content you create (habits, journal entries, messages), and grant us a limited licence to store and process it to provide the Service.
Disclaimer of warranties
The App is provided "as is" without warranties of any kind, express or implied. We do not warrant that the App will be error-free, uninterrupted, or that AI coaching responses will be accurate or complete.
Limitation of liability
To the fullest extent permitted by law, we are not liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of the App. Our total liability to you for any claim shall not exceed the amount you paid us in the 12 months preceding the claim.
Termination
You may stop using the App and delete your account at any time from Settings. We may suspend or terminate your access if you violate these Terms, with reasonable notice where practicable. On termination, your data will be deleted in accordance with our Privacy Policy.
Governing law
These Terms are governed by the laws of the State of California, USA, without regard to conflict of law principles. Any disputes shall be resolved in the courts of San Francisco County, California, unless otherwise required by applicable consumer protection law in your jurisdiction.
Changes to these Terms
We may update these Terms from time to time. If we make material changes, we will notify you through the App or by email before the changes take effect. Continued use of the App after changes constitutes acceptance of the updated Terms.
Contact
Questions about these Terms? Email kael6688@proton.me