Terms of Service

Last updated: October 13, 2026

These Terms of Service ("Terms") govern your use of the Athylos iPhone and Apple Watch apps, the Athylos website, and related services (together, the "Service"). By creating an account or using the Service, you agree to these Terms. If you do not agree, do not use the Service.

1. What Athylos is — and is not

Athylos generates swim workouts using artificial intelligence, sends them to your Apple Watch, and analyzes your training data. Athylos provides training guidance only. It is not medical advice, and it is not a substitute for a qualified coach, physician, or lifeguard.

• Consult a physician before beginning any training program, especially if you have a medical condition or are returning from injury.
• Swimming carries inherent risk. Always swim in supervised facilities, follow posted rules, and never swim alone.
• AI-generated workouts may not be appropriate for your ability level. Use your own judgment, scale or skip anything that feels unsafe, and stop if you feel unwell.

You assume full responsibility for your training decisions and physical activity.

2. Eligibility and accounts

You must be at least 13 years old to use the Service. You sign in using Sign in with Apple; you are responsible for maintaining the security of your Apple ID and for all activity under your account. You may delete your account at any time in Settings → Delete Account.

3. Subscriptions and billing

Athylos offers a free plan and one paid plan, Athylos Swimmer.

Free plan. Free accounts generate up to 5 workouts a month and 2 a week, whichever limit is reached first, and 30 coaching messages a month.

Athylos Swimmer is an auto-renewing subscription at $9.99 a month or $99.99 a year, billed monthly or yearly to your Apple ID. It includes a one-month free trial when your Apple ID is eligible. You are charged when the trial ends unless you cancel at least 24 hours before. Paid plans:

• Are billed to your Apple ID through the App Store. Athylos never sees or stores your payment details.
• Renew automatically each billing period unless cancelled at least 24 hours before the end of the current period.
• Can be managed or cancelled at any time in your Apple ID settings (Settings → Apple ID → Subscriptions on your iPhone).
• Are refundable only through Apple, per Apple's refund policies.

Fair use on Swimmer. A Swimmer subscription includes 300 AI generations and coaching actions a month. The allowance covers workout generation and coaching chat together, and it exists so one account cannot run up unbounded model cost. It resets on the 1st of each month, and Settings → Usage shows where you stand before you get near it. Ordinary daily training does not reach it. If you do reach it, the rest of the app — your history, analytics, saved workouts, and Watch sync — keeps working.

Current prices, exact free-tier limits, and trial length are published at athylos.com/pricing.

Prices and tier features may change; we will give notice of price changes as required by Apple, and changes will not apply until your next renewal.

4. Acceptable use

You agree not to:

• Reverse engineer, copy, resell, or create derivative works of the Service, except as permitted by law;
• Use the Service to build a competing dataset or train competing models;
• Probe, overload, or disrupt our systems, or attempt to access accounts or data that are not yours;
• Use the Service in violation of any applicable law.

5. Your data and our license

You own your training data. You grant us the license needed to operate the Service: storing your data, processing it to generate workouts and analytics, and displaying it back to you. If you opt in to analytics sharing, you also grant us the right to use that pseudonymous data to improve Athylos. How we collect and handle data is described in our Privacy Policy.

6. No affiliation with athletes, coaches, or programs

Athylos is not affiliated with, endorsed by, or sponsored by any swimmer, coach, team, or program. If you ask for a session in the style of a named coach, program, or era, Athylos writes an original workout informed by publicly known information about that approach. It does not reproduce anyone's actual training, and naming someone does not mean they were involved.

7. Intellectual property

The Service — including the apps, design, branding, and underlying technology — is owned by Athylos and protected by intellectual-property laws. These Terms grant you a personal, non-exclusive, non-transferable, revocable license to use the apps on Apple devices you own or control, as permitted by the App Store terms.

8. Termination

You may stop using the Service or delete your account at any time. We may suspend or terminate your access if you violate these Terms, if required by law, or if we discontinue the Service. Sections 1, 5, 9, 10, and 11 survive termination.

9. Disclaimers

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 WORKOUTS, PACE TARGETS, OR ANALYTICS ARE ACCURATE, COMPLETE, OR SUITABLE FOR YOU, OR THAT THE SERVICE WILL BE UNINTERRUPTED OR ERROR-FREE.

10. Limitation of liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, ATHYLOS WILL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR FOR ANY PERSONAL INJURY ARISING FROM YOUR PHYSICAL ACTIVITY, LOSS OF DATA, OR LOSS OF PROFITS, ARISING OUT OF OR RELATED TO YOUR USE OF THE SERVICE. OUR TOTAL LIABILITY FOR ANY CLAIM WILL NOT EXCEED THE GREATER OF $50 OR THE AMOUNT YOU PAID US IN THE TWELVE MONTHS BEFORE THE CLAIM AROSE. Some jurisdictions do not allow certain limitations, so some of the above may not apply to you.

11. Governing law and disputes

These Terms are governed by the laws of the United States and the State of New York, without regard to conflict-of-law rules. Disputes will be resolved in the state or federal courts located in New York County, New York, and you consent to their jurisdiction.

12. Changes to these Terms

We may update these Terms as the Service evolves. If changes are material, we will update the date above and notify you in the app or by email before they take effect. Continued use after changes take effect means you accept the updated Terms.

13. Contact

Questions about these Terms? Email support@athylos.com or use Settings → Contact Support in the app.