demi.st
Terms of Service
Last updated 16 October 2026
Provider
OATFOX LTD (“we”), a company registered in England and Wales; company number 17519607, registered office 71-75 Shelton Street, London WC2H 9JQ, United Kingdom. Contact: support@demi.st. Our Privacy Policy says what we store.
1. What demi.st is
demi.st records what you log and shows it back. It is a record, not a treatment: it makes no health claims, does not diagnose or treat anything, and is no substitute for a doctor, a pharmacist or a stop-smoking service. Do not use it in an emergency.
2. Age
You must be 18 or over, or the legal age for vaping products where you live if that is higher.
3. Licence
We grant you a limited, non-exclusive, non-transferable, revocable licence to install and use demi.st for your personal use, subject to these terms and the rules of the app store you got it from. You must not copy, modify, resell, distribute, reverse-engineer or attempt to extract the source code of the app, except where the law allows.
4. Your history
There are no accounts. Your history is tied to random identifiers on your phone, and a recovery key or a sign-in, made from Preferences › Keep your history, brings it back on another phone. Anyone with your key can move your history to their phone. We cannot recover a lost key; a phone that still has the history can make a new one, which replaces the old. A reinstall without a key or a sign-in starts a new history. Delete history cannot be undone; the Privacy Policy says what it does.
5. The chat
Answers in the chat are written by an AI model from a summary of your logs. They can be wrong and are not advice. We may limit the number of questions in a day.
6. Price
demi.st is free. If we introduce paid features we will say so before you pay, and the app store will handle payment under its terms.
7. Acceptable use
You must not use demi.st unlawfully, infringe anyone’s intellectual property or privacy, interfere with or disrupt the app, the website or the systems behind them, bypass security or reach their non-public parts, or upload malware or harmful code.
8. Intellectual property
demi.st, its wordmark and everything in the app and on the website belong to us or our licensors. Apart from the licence in section 3, no rights are granted to you. What you log is yours.
9. Third-party services
demi.st relies on services run by others: the app stores, the sign-in providers, an AI model provider and our hosting providers. Their own terms govern them, and we are not responsible for them.
10. Updates and availability
We may change, suspend or withdraw features at any time, and may require you to install an update to keep using the app. We do not promise that the service is always available.
11. Disclaimer and limitation of liability
The demi.st app and website are provided “as is” and “as available”. To the extent the law allows, we exclude all warranties and conditions not set out in these terms, and we are not liable for any indirect, incidental, special or consequential loss, loss of data, loss of profits or business interruption. Where liability cannot be excluded it is limited to direct losses and, in any event, to the amount you paid us in the twelve months before the claim, if any. Nothing in these terms limits liability for death or personal injury caused by negligence, for fraud or fraudulent misrepresentation, or for anything else that cannot be limited by law. Your statutory rights as a consumer are not affected.
12. Termination
You can stop using demi.st at any time. We may suspend or end your access if you breach these terms, if the law requires it or if we withdraw the app, and the licence in section 3 then ends.
13. Governing law
These terms are governed by the law of England and Wales, and its courts have jurisdiction. If you live elsewhere you keep the protection of the mandatory consumer laws of your country and may bring a claim in your local courts.
14. Changes
The latest version of these terms is at demi.st/terms with its date at the top. Continuing to use demi.st after a change takes effect means you accept it.