Rheostat

Terms of Service

Last updated: 23 August 2026

These terms govern your use of the Rheostat iPhone app, published by Lacaro Ventures LLC ("we", "us"), 5900 Balcones Dr, Ste 100, Austin, TX, United States. By downloading or using the app, you agree to them.

Rheostat is not a medical device.

It is intended for general wellness and fitness purposes only. It is not designed, tested, or approved to diagnose, treat, cure, monitor, or prevent any disease or medical condition, and it has not been evaluated by the FDA or any comparable authority.

Readiness and Strain are estimates derived from consumer wearable sensors. They can be wrong. Never use Rheostat to make a medical decision, and never let it delay you seeking care. If you have a health concern, or before beginning any new exercise programme, talk to a qualified healthcare professional. If you think you may be having a medical emergency, contact emergency services immediately.

Using the app

We grant you a personal, non-transferable, non-exclusive licence to use Rheostat on Apple devices you own or control, consistent with the App Store Terms of Service. You agree not to reverse engineer, decompile, resell, or redistribute the app except as permitted by law.

Health data and accuracy

Rheostat reads data you choose to share from Apple Health and processes it entirely on your device. The quality of its output depends on the quality and completeness of that input. Missing nights, an unworn watch, or sensor error will produce inaccurate scores.

The app compares your data against your own history. In your first weeks of use, or after a long gap, scores are directional rather than precise. We make no warranty that scores are accurate, complete, or suitable for any particular purpose.

Subscriptions

Your content and data

Your health data is yours. We never receive it. See our Privacy Policy.

Changes to the app

We may add, change, or remove features, and may update the scoring algorithms as they improve. Algorithm changes can shift your scores relative to previous days. We'll note significant changes in release notes.

Disclaimer of warranties

The app is provided "as is" and "as available", without warranties of any kind, express or implied, including merchantability, fitness for a particular purpose, and non-infringement. We do not warrant that the app will be uninterrupted, error-free, or that any defect will be corrected.

Limitation of liability

To the fullest extent permitted by law, Lacaro Ventures LLC is not liable for any indirect, incidental, special, consequential, or punitive damages, or for any loss of profits, data, or goodwill, arising from your use of or inability to use the app — including any injury, health outcome, or training decision made in reliance on it. Our total aggregate liability is limited to the amount you paid us for the app in the twelve months preceding the claim.

Some jurisdictions do not allow certain limitations, so parts of this section may not apply to you.

Termination

You may stop using the app at any time by deleting it. We may suspend or terminate access if you breach these terms.

Governing law

These terms are governed by the laws of the State of Texas, United States, without regard to its conflict-of-laws rules. Nothing here limits consumer protection rights you may have where you live.

Apple

Apple is not a party to these terms and has no responsibility for the app. Apple has no obligation to provide support or maintenance. In the event of any failure to conform to warranty, you may notify Apple for a refund of the purchase price; Apple has no other warranty obligation. Apple and its subsidiaries are third-party beneficiaries of these terms and may enforce them against you.

Contact

support@lacaroventures.com

Lacaro Ventures LLC
5900 Balcones Dr, Ste 100
Austin, TX, United States