Privacy Policy
Last updated November 7, 2026. FastKept is in development; we will update this policy before launch if anything below changes.
This policy covers the iPhone and Android apps. Where a section mentions your iPhone, Apple Health, Sign in with Apple or Apple purchases, it describes the iPhone app; the Android app is described in its Android sections.
This policy explains how FastKept (the iPhone and Android apps and fastkept.com) handles information. The app is operated by Solstice Labs LLC, a Colorado limited liability company, 215 S Wadsworth Blvd Ste 400, Lakewood, CO 80226 ("we").
Summary
Fasting records, plans and logs are stored on your iPhone, and every feature works without an account. On iPhone, if you choose the optional account and tap Back up, a copy is kept with your account so you can restore it. CSV export is always available.
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.
Your fasts, weight and any health data stay on your device (and your private iCloud if you turn on sync) and are never used for advertising or sold.
Apple Health access is optional, asked for with your permission, and can be removed at any time.
We don't ask for or store medical conditions; the cautions are information only.
Information we collect
- If you purchase the optional supporter subscription: purchase and subscription status
- If you choose to create the optional account: your email or Sign in with Apple identifier, and the name Apple shares if you allow it
Information we do not collect
- Your fasting times, history, schedules or logs, unless you choose the optional backup
- Progress photos
- Location, contacts or advertising identifiers
Health information
FastKept is a timer and log, not medical advice. It does not measure ketosis, autophagy or any other body state. Fasting isn't right for everyone. Talk to a doctor or other qualified professional before fasting, especially if you have a health condition, take medication, are pregnant or breastfeeding, or have a history of disordered eating.
Optional account
You can use every feature without an account. The Android app has no account. On iPhone, if you choose to sign up (with email or Sign in with Apple, 18 or older only), one account works in all of our apps. We store your email or Apple sign-in identifier, which of our apps you've signed in to, your marketing and beta choices in each app with the time you made them, and an optional backup of each app's settings and records. If you tap Back up, the backup includes your fasts, plans and logs, including weight entries read from Apple Health, so you can restore them. Progress photos are never included, and nothing is backed up unless you choose to. If you have an ad-free subscription, we also store its end date and Apple's transaction identifier (checked against Apple's signature) with your account. You can sign out, turn choices off, or delete your account any time from Profile; deleting it removes it and its backups in all of our apps. See our suite account page for what the shared account stores and how to delete it.
If you sign in with a verified email address or Apple ID that also belongs to a NearbyGrid account, our accounts server checks whether that NearbyGrid account is in good standing and was active in the past 7 days. If it was, your Solstice Suite apps are ad-free until 7 days after that activity. The only result the check gives is whether you qualify and until when; that date is held briefly in the server's memory (up to 10 minutes), is not saved to your suite account, and no other NearbyGrid information is shared with the suite apps.
Our apps on your iPhone
To avoid promoting apps you already have, the app checks whether our other apps are installed on your iPhone. It can only check for our own apps, and the result stays on your device. If you buy an ad-free subscription, the app saves its end date in a place only our apps can read, so our other apps on the same iPhone can turn ads off too.
iOS permissions
- Apple Health (optional) — Reads your weight from Apple Health, and saves the weight and water you log, only if you turn on Apple Health in Settings.
- Face ID (optional) — Can ask for Face ID before showing your history, only if you turn on App lock in Settings.
- Notifications (optional) — For local reminders you set. Declining them doesn't affect the timer or history.
Android permissions
On Android, everything above that mentions your iPhone applies to your Android phone, except the optional account, which the Android app does not have. Apple Health, iCloud and Face ID are not used; Health Connect is used instead.
- Health Connect (optional): reads your weight, and saves the weight and water you log, only if you turn on Health Connect in Settings. You can remove access at any time in your phone's settings.
- Notifications (optional): for reminders you set and the running fast timer. Declining them doesn't affect the timer or history.
- Ongoing notification: shows your running fast's timer in your notifications while a fast is in progress, with End fast. It doesn't read or send anything else.
- Google Play Billing: processes the optional supporter subscription. We receive purchase status, never your payment details.
Android app: purchases, diagnostics and network
Purchases. The optional subscription is sold through Google Play. Google processes the payment; RevenueCat receives the purchase receipt and subscription status so the app can restore the supporter state on another install signed into the same Google Play account. The app creates no account, and RevenueCat's automatic device-identifier collection is disabled.
Crash and diagnostic reports. If the app crashes or reports a handled error, Sentry receives a report with the stack trace, app version, device model and Android version, plus a short diagnostic trail of screens, fixed action codes and network events (URLs without query strings). Sentry's automatic personal-data collection is off; the app never attaches a user identity, screenshots, view hierarchy, cookies or request headers, and there is no advertising identifier. It does not include your fasts, weight, water or other app content.
Network. The app still works with no connection. A connection is used to load subscription products, validate or restore a purchase, and send crash and diagnostic reports (including Sentry sessions/performance).
Ads. We show only promotions for our own apps; we do not show third-party ads. The $19.99/year subscription removes those promotions.
Service providers
We use a small number of providers only to run the app. They may not use your information for their own purposes.
- RevenueCat — Processing the optional supporter subscription and restoring purchases. It does not receive your app content.
- Sentry — crash and performance diagnostics via Sentry; no account, email or content
Advertising
Any ads in our apps promote only our own apps. We do not sell personal information, do not share it for cross-app advertising, and do not use Apple's advertising identifier to track you. The Android app has no advertising identifier.
Purchases
On iPhone, optional supporter subscriptions are processed by Apple. On Android, they are sold through Google Play. We receive purchase status (for example, whether a subscription is active) but never your payment card details.
This website
This website (fastkept.com) uses Cloudflare Web Analytics to count page views. The counter sets no cookies, stores nothing on your device and does not build a profile of you across sites. Cloudflare hosts this website: it receives the page address, referring page and browser type of each visit to produce these counts, and it processes standard request logs to serve the pages. See Cloudflare's privacy policy. This website does not use Google Analytics or advertising cookies. What the app itself collects is described in the rest of this policy.
Children
The app is not directed to children under 13, and we do not knowingly collect their personal information.
Your choices and rights
You can use the app without an account, turn off notifications and permissions in iPhone Settings, and delete local data by deleting the app. To access or delete information connected to you, email privacy@solsticesuiteapps.com. Depending on where you live (for example, the EU, UK or California), you may have additional rights, and we will honor them.
Retention and security
We keep information only as long as needed for the purposes above and protect it with reasonable safeguards.
Changes
We will post changes here and update the date above.