Terms of use

Last updated 17 October 2026

The service

Lack is free. We may add paid features later; nothing you can do today will be moved behind a paywall without notice.

Not medical advice

Scores, predictions and suggestions in Lack are estimates computed from consumer wearable data using published methods. They are for general wellness only. They are not medical advice, not a diagnosis, and not a contraceptive or fertility method. Talk to a clinician before changing medication, training through pain, or acting on any signal that worries you.

Your account

You need to be 13 or older. Keep your credentials to yourself; you are responsible for activity on your account. You can delete it at any time from You → Account.

Your content

Your data is yours. You give us only the licence needed to store it, sync it and show it to the friends you choose. We can remove content that is illegal or abusive.

Acceptable use

Do not use Lack to harass others, impersonate anyone, scrape data, or interfere with the service. Friend requests must be accepted by the other person before anything is shared.

Availability and liability

We aim for the service to be reliable but provide it as is, without warranties. To the extent the law allows, we are not liable for indirect losses or for decisions you make based on the app. Nothing in these terms limits liability that cannot be limited by law.

Changes and termination

We may update these terms and the app; continued use after a change means you accept it. We may suspend accounts that break these terms.

Contact

Lack · [email protected]