Terms of Use
Last updated September 27, 2026.
These terms apply to FastKept and fastkept.com, operated by Solstice Labs LLC, a Colorado limited liability company, 215 S Wadsworth Blvd Ste 400, Lakewood, CO 80226. Apple's Licensed Application End User License Agreement (Standard EULA) also applies to the iPhone app; if these terms conflict with it, the Standard EULA controls for the app.
Free features and optional subscription
ALL FEATURES ARE FREE. Use the app without an account. We only ever show ads for our own apps, and they are occasional and dismissible. An optional subscription removes all ads and automatic signup reminders in all of our apps on your iPhone. Every feature stays free either way. Subscriptions renew automatically until cancelled in your Apple account settings at least 24 hours before renewal. Prices are shown in the App Store before purchase.
Important information
FastKept helps you time and record fasts. It gives general information only and doesn't provide medical advice, diagnosis or treatment. Fasting isn't suitable for everyone. Please don't use FastKept if you are under 18, pregnant or breastfeeding, underweight, or have or have had an eating disorder. Talk to a doctor before you start or change a fasting routine if you have diabetes or low blood sugar, a heart, kidney or other medical condition, take medication, or are older. We suggest getting medical guidance before any fast longer than 24 hours. Drink water, and stop fasting and eat if you feel dizzy, faint, shaky, confused or unwell. Fasting stages and any figures shown are general estimates, not measurements of your body.
- Not medical advice; talk to a doctor before starting or changing a fasting routine.
- Not for people under 18, pregnant, breastfeeding or trying to conceive, or underweight.
- Not for anyone with a current or past eating disorder; if tracking fasts feels stressful or compulsive, please pause and reach out for support.
- Check with a doctor first if you have diabetes (type 1 or 2), low blood sugar, heart, kidney or liver conditions, gout, a history of fainting, or take medicines such as insulin or blood-pressure tablets.
- Get medical guidance before fasting longer than 24 hours; FastKept does not encourage extended or multi-day fasts.
- Stop and eat if you feel dizzy, faint, shaky, confused or unwell; seek urgent help if symptoms are severe.
- Stay hydrated; the app's fasting stages are general estimates, not readings of your body.
FastKept is a tracking tool for adults aged 18 and over. It does not provide medical, nutritional or dietary advice, and no clinical relationship is created by using it.
Fasting carries risks for some people. By using the app you agree to consult a qualified health professional before fasting if any of the listed conditions apply to you.
Fasting stage descriptions, timers and any weight or health figures are general estimates for information only.
The app is not for emergencies. If you feel seriously unwell, contact your local emergency number.
The optional ad-free plan renews automatically until you cancel it in your Apple ID settings at least 24 hours before the period ends; deleting the app does not cancel it.
Every feature works without an account or payment. Creating an optional account requires being 18 or older.
Promotions inside the app are only for our own apps and never use your health, photo, screen-time or list data.
Our apps work together
One optional account for all our apps. Our apps (Offline Streak, WatchHRV, FastKept, Breathe for Five., Stick to Plan, Payoff, Save and Words to Lift You) share one optional account. Signing in with the same email or Apple ID in another of our apps uses the same account, so you won't be asked to confirm your age again. Deleting your account deletes it, and its online backups, in all of our apps. Deleting an account does not cancel an App Store subscription; manage that in your Apple account settings.
Ad-free in every app. An ad-free subscription bought in any one of our apps removes ads in all of our apps installed on the same iPhone. Our other apps learn the subscription's current end date when the app you bought it in is opened. If you don't open that app for a while after a renewal, ads may reappear in our other apps until you open it or tap Restore Purchases there.
Acceptable use
Don't misuse the app, attempt to disrupt it, or use it to break the law.
Not professional advice
FastKept provides general tools and information only. It is not medical, legal or other professional advice.
Disclaimer and liability
The app is provided "as is" to the extent permitted by law. To the extent permitted by law, we are not liable for indirect or consequential damages.
Changes
We may update these terms and will post the new version here.