Privacy Policy

Last updated October 9, 2026

FuelKey (nutrition) and LiftKey (lifting) are operated by Keystone Athletics & Iron LLC ("we", "us"). This policy explains what we collect when you use either app or their websites, and what we do with it. Both apps share one account, so this one policy covers both.

What we collect

• Account details: your email address and, if you sign in with Apple or Google, the name and email they share with us.
• What you tell the intake: sex, age, height, weight, activity level, training frequency, goal, pace, diet and foods you avoid. We use these only to calculate your targets and build your plan.
• What you log: meals eaten or skipped, foods you add, weigh-ins, notes, your meal plan, shopping list and prices you enter.
• Imported history (only if you choose to import): past body weights read from Apple Health on your iPhone, past weigh-ins you type in, and the weigh-ins and most-logged foods found in an export file from another app. Export files are read on your own device; only the weigh-ins (date and weight) and the foods you keep are saved to your account.
• Purchases: which plan you're on and its status. Card details are handled by Stripe (web) or Apple and Google (apps); we never see or store your full card number.
• Basic technical data: device type, error messages and, in LiftKey, a diagnostics report that contains only counts (for example how many workouts are saved), needed to keep the apps working.
• Problem reports: the note you write when you use Report a problem, plus the app version and device type, so we can fix it.
• App release lists: which phone you use (iPhone or Android), so we can tell you when its app is released. If you join a list on our websites without an account (fuelkey.app or liftkey.app), we keep only your email address and, for FuelKey, your phone type.

How we use it

• To run FuelKey: calculate targets, build plans, save your log, and sync it across your devices.
• To manage your subscription or Founder purchase.
• To send account emails (sign-in, password reset, receipts) and, if you turn them on, meal and trial reminders.
• To email you once when the FuelKey app for your phone is released, if you joined the list or told us your phone. To be removed, email support@keystoneathleticsandiron.com.
• To fix problems and improve the app.

We do not sell your personal information, and we don't use your health or food data for advertising.

Who processes it for us

We use a small number of providers who handle data only to provide their service to us:

• Supabase: database, sign-in and hosting of your account data (United States).
• Vercel: website hosting, and anonymous visit counts (pages viewed, the site you came from, country, device type). No cookies, and nothing that identifies you.
• Stripe: payments on the web. Apple and Google: purchases in the apps. RevenueCat: confirms app store purchases and renewals for us (your account ID and purchase receipts only).
• Resend: account emails.
• Anthropic or Google (Gemini): when you use "Estimate a meal out", "Snap a photo" or "What fits here?", what you type (a meal description, where you are, any calorie count you enter), the photo you take for "Snap a photo", and for "What fits here?" your remaining calories and protein and any diet or foods you avoid, are sent to produce the answer. Photos are used only for that estimate and are not stored by FuelKey. Your name, email and other data are not sent.
• Open Food Facts: when you scan or type a barcode, the barcode number is sent to look up the product. Nothing identifying you is sent.
• USDA FoodData Central and Open Food Facts: when you use food search, the words you search for are sent through our server to these public food databases. Nothing identifying you is sent.

Health Connect: smart scales and workouts (Android)

FuelKey reads from Health Connect only what you turn on in the Android app, and only after you allow it there. It never writes to Health Connect.

• Use my smart scale: FuelKey reads your body weight, where smart scale apps save your weigh-ins. Weights you typed into a health app by hand are skipped. FuelKey keeps your first morning and last evening weigh-in each day in your FuelKey account so your weekly review can see your trend; other readings are not stored.
• Workouts: FuelKey reads your recorded exercise sessions and the active calories burned during them, so a workout can raise that day's calorie target. For each workout of 10 minutes or more it keeps the date, the type of workout, the app that recorded it, its start and end time, its length and the active calories. Nothing else from Health Connect is read.

Data from Health Connect is used only to provide these features, is never used for advertising, never sold, and never shared with anyone else. You can turn either one off any time in FuelKey or in Health Connect's settings, and delete it with your account (see below). FuelKey's use of information received from Health Connect follows the Health Connect Permissions policy, including its Limited Use requirements.

Apple Health (iPhone)

FuelKey reads from Apple Health only what you turn on in the iPhone app, and only after you allow it in the Health permission screen. It never writes to Apple Health.

• Import weight from Apple Health: reads your past body weight once, to fill in your weight history.
• Use my smart scale: reads new body-weight readings that your scale saves to Apple Health, also in the background. Weights typed into the Health app by hand are skipped. FuelKey keeps your first morning and last evening weigh-in each day; other readings are not stored.
• Workouts: reads your recorded workouts and their active calories, so a workout can raise that day's calorie target. For each workout of 10 minutes or more it keeps the date, the type of workout, the app that recorded it, its start and end time, its length and the active calories.

Data from Apple Health is never used for advertising or marketing, never sold, and never shared with anyone except the providers above that store your account. You can turn access off at any time in FuelKey, or in the Health app under Sharing, then Apps.

LiftKey

When you use LiftKey we collect:

• Your workouts: the exercises, sets, weights, reps and times you log, your routines, streak, rest timer settings, and the equipment or band levels you choose when you adapt a day.
• Body weight: the body weight you enter, used to estimate calories burned. If you turn it on, LiftKey also reads your FuelKey weigh-ins from the same account.

“Go easy on” choices you pick by hand (for example knees or shoulders) stay on your device and are never sent to us. If you use “Adapt today with AI”, what you type about your day (for example your equipment, your time, or a sore area) is sent to Anthropic, our AI provider, only to set that day’s workout options, then discarded: we don’t store it or keep it in logs, and your name and email are not sent with it. On Apple Watch, heart rate and calories stay in Apple Health on your devices; only the workout itself is saved to your account.

If you use both apps, FuelKey reads the workouts you log in LiftKey (the day, how many sets, how long it took and the estimated calories burned) to adjust that day's target. Nothing is shared with anyone outside Keystone Athletics & Iron.

How long we keep it

We keep your data while your account exists, including after a trial ends or a subscription lapses, so you can pick up where you left off. If you delete your account, we delete your personal data within 30 days, except records we're required to keep for tax or legal reasons (for example, payment records).

Your choices and rights

• Delete your account and everything in it yourself, any time: in the iPhone app under Account, or in the Android app and on the website at the bottom of the app page (Delete account). Can’t sign in? Email support@keystoneathleticsandiron.com from your account’s address and we’ll delete it for you. Subscriptions billed through the website are cancelled automatically when you delete your account.
• Access, correct or export your data: email support@keystoneathleticsandiron.com.
• Turn reminders off in the app or in your device settings.
• Depending on where you live (for example California or the EU), you may have additional rights; we honor those requests the same way.

Security

Data is encrypted in transit, every account can only read its own data, and payment details stay with the payment providers. No system is perfectly secure, but we work to protect your information.

Children

FuelKey and LiftKey are not intended for anyone under 16, and we don't knowingly collect data from children.

Health information

FuelKey and LiftKey record what you tell them and do arithmetic. They are not medical services, and nothing in them is medical, dietary or exercise advice.

If you’re outside the US

FuelKey is run from the United States. Your account data is stored and processed in the US by the providers listed above (Supabase for the database, Vercel for the website, and Anthropic or Google for the AI features). If you use FuelKey from Canada, Australia or elsewhere, your data is transferred to and stored in the US, where privacy law may differ from yours. We protect it the same way everywhere: encrypted in transit, used only to run the app, and never sold.

Person responsible for privacy: Evan Schirra, Owner, Keystone Athletics & Iron LLC, support@keystoneathleticsandiron.com. Contact us first with any question or complaint about your data; we answer within 30 days.

If you’re not satisfied with our answer, you can contact your privacy regulator: in Canada, the Office of the Privacy Commissioner of Canada (in Quebec, the Commission d’accès à l’information); in Australia, the Office of the Australian Information Commissioner.

Changes

If we change this policy in a meaningful way, we'll update the date above and let you know in the app or by email.

Contact

Keystone Athletics & Iron LLC · support@keystoneathleticsandiron.com · keystoneathleticsandiron.com