What this policy covers
This policy covers the Metrion iPhone app, its Apple Watch app, and metrion.fit. “We”, “us”, and “our” refer to the operator named in the contact details on this page. The website introduces an app that is in early access through TestFlight; its interactive workouts and coach responses are illustrative.
The app is designed to work without a Metrion account. We do not receive or keep a server-side copy of your Apple Health data, training history, or coaching notes. If you agree to it, the AI coach sends a capped packet of training facts through a relay we operate so a model can answer; see “The AI coach” below for exactly what that packet holds and how to turn it off. Visiting the website or contacting us is different: delivery providers process technical request information, and we receive any information you choose to send us.
Health information the app reads
With your permission, Metrion reads relevant information from Apple Health to describe your training, estimate recovery, and build your plan. Depending on the permissions you grant and the data available, this includes:
- Workouts, their activity types and duration, heart rate, effort scores, steps, exercise minutes, distance, and active energy.
- Heart rate variability, resting and walking heart rate, aerobic fitness estimates, sleep, breathing rate, and wrist temperature.
- Birth date, sex, height, and weight to support your profile and training calculations, and any body-fat percentage, lean body mass and body mass index to follow your goal measurements.
- Cycle information only when you enable the optional cycle feature and grant the relevant Health permission.
Sleep includes the nights other apps save to Apple Health. Where your watch and another app recorded the same minutes, Metrion counts the watch’s. If you tell Metrion that a night was a nap or that your watch missed some sleep, that answer stays on your phone and changes only what Metrion reads.
You can also enter preferences such as your goals, usual training days, available time, and a heart-rate override. The app processes these together with the Health information you authorise. Missing permissions or readings may limit particular insights.
Metrion never deletes records in Apple Health, and it never writes anything it worked out for you. The only things it writes are workouts. A walk or run you record with the Metrion Apple Watch app is saved by the watch as one workout, with its heart rate, energy, distance and, if you leave route recording on, its route. While it records, the watch reads your heart rate, distance and energy to show your zone against the plan, and it uses your location only for the route, which you can turn off in the app’s settings on your phone. The watch sends the finished session to your iPhone and to nobody else.
A strength session you follow in the app is saved as one Traditional Strength Training workout, with its start and end time. If your watch recorded the session, the watch saves it with your heart rate and energy; if not, your iPhone saves it with no heart rate. During the session the watch shows your heart rate and the rest countdown, and a set you log on the watch goes to your iPhone and to nobody else. Health gets the workout only.
Strength training
If you use strength training, Metrion keeps the muscles you chose and the words you used for them, your equipment, each set you log with its exercise, reps and weight, the weight and reps each exercise is at, any change you made to a session, and any pain you reported with the words you gave. All of it stays on your phone, none of it is written to Apple Health, and Delete all data removes it. The exercise demonstrations are bundled with the app, so watching one sends nothing.
Where your information goes
The app stores its profile, workout summaries, calculated metrics, plans, and saved coaching notes locally on your device. It does not operate a Metrion cloud account or sync service. Health information is never sent to advertising networks or data brokers, and we do not sell it or use it for advertising. The only training and health information that leaves your phone is the coach’s summary described below, and only after you have agreed to it.
The AI coach
Metrion’s coach writes in two places, and you choose whether the second one is used.
You are asked first. When you set up Metrion, after you connect Apple Health, the app asks whether the coach may send a summary of your training to be read. It says what is sent, who receives it and why, and offers two answers: turn on the coach, or keep everything on the phone. An install set up before this question existed is asked once, on its next launch. Nothing is sent to the relay before you answer, and nothing is sent at all if you choose to keep it on the phone.
On your device. Your day’s decision, your plan’s reasons, every workout review and the coach’s own questions can all be written on the phone, using Apple’s on-device Foundation Models framework where it is available and locally generated template text where it is not.
Through our relay. For the fuller answers, meaning the coach conversation, the written workout review, the weekly verdict and the monthly, quarterly and yearly reviews, the app sends an evidence packet and, in a conversation, the question you typed, to a relay service we operate. The relay adds the model key and forwards one request to a Claude model made by Anthropic, reached through Quant’s AI gateway.
The evidence packet is a short, capped set of facts about your training: numbers and plain sentences such as session minutes, training load, heart-rate summaries, sleep hours, readiness, your stated goals and your recent plan. When a question is about strength, the coach also reads a strength summary: the muscles you chose and your words for them, this week’s sets against their targets, the weight and reps each exercise is at, how your weights moved over the last eight weeks, and any pain you reported, as the exercise and the area, without the words you wrote about it. It carries no name, no email address, no account identifier and no contact details, because the app does not have any. To prove the request comes from a genuine, unmodified copy of Metrion, the app also sends an Apple App Attest key identifier and, if you subscribe, the App Store’s own signed transaction.
Our relay stores no question, no answer and no health measurement. It keeps the App Attest key identifier, a signature counter, a count of calls, and one usage row per call carrying the model, the token counts and the cost under a one-way hash that cannot be joined back to an install. So the full list of who sees a coach packet is short: our relay, which runs on Quant Cloud and keeps none of it; Quant’s AI gateway, which passes it on and does not log it or train on it; and Anthropic, which answers it. Nothing else receives it, and we keep nothing of it beyond the usage row described above, which holds no health value.
The same protection, all the way through. We send the coach packet only to services that protect it at least as well as this policy does. Quant and Anthropic may use it only to answer your request. Neither may sell it, use it for advertising, or use it to train AI models, and each keeps it secure under its own terms with us. Their processing may occur outside your country. If we ever add or change a service that receives the packet, we will name it here before it receives anything.
The AI coach switch in the You tab holds the same answer, so you can change it at any time. With it off nothing is sent, every screen falls back to the on-device coach, and the app does not ask you to turn it back on. Delete all data also clears your answer, so a new setup asks again. We do not use your health information or coaching text to train our own AI models.
The totals we publish
We publish a few totals about Metrion itself: how many hours of training it has read, how many workouts, how far people have walked and run, and how many questions the coach has answered. So that those numbers are true rather than guessed, the app counts them and sends them in.
What is sent. Once a week, and no more often, the app sends three whole numbers: how many workouts it has read since it last sent anything, how many minutes those workouts lasted, and how many metres of that was walking, running or hiking. There is no date, no activity, no heart rate, no pace, no place, no session and nothing that could be put back together into a week of your training.
What happens to it. The relay adds each number into a running total that already holds everybody, and then keeps nothing of the contribution. No record anywhere pairs your device with an amount of training. The relay also counts how many copies of the app have ever sent anything, so we can say how many athletes those totals come from.
What is published. The public totals are frozen for a day at a time, so watching them cannot follow any one person’s week. Every number is rounded down. And we publish no numbers at all until at least twenty-five people have been counted, because below that a total says too much about one person’s training. We may raise that floor, and we will never lower it.
Turning it off. The one AI coach switch above governs this too, so nothing is counted until you have said yes to the coach. With it off, nothing is counted and nothing is sent. It costs none of your monthly coach replies, and a contribution that fails is dropped rather than retried, so the totals we publish are a floor and never an over-claim.
Weather
To tell you when the heat should change a session, the app uses your approximate location while it is open, at about one kilometre of accuracy. It asks on the Notes and weather step of setup. If you skip it there, iOS may ask again the first time Today opens. It never tracks you in the background. The app asks Apple’s WeatherKit for the temperature and humidity at that place. The request carries no health information and nothing that names you, and Metrion keeps no record of where you were. If you do not allow location, the app says nothing about the weather, and every other screen still works.
The app no longer reads air quality. Test builds before 30 September 2026 sent a position rounded to one decimal place, about eleven kilometres, to Open-Meteo’s air quality service. The app now sends nothing to Open-Meteo or to any other air quality service. If we bring air quality back, we will say so here before the app sends anything.
Apple’s Health storage, device transfers, backups, and platform services are managed by Apple and your device settings. This policy describes Metrion’s own processing; it does not replace Apple’s privacy policy.
Your choices and deletion
You can review or withdraw Metrion’s access in Apple Health’s app permissions. Withdrawing permission stops future access to the affected data; it does not automatically remove information already imported into Metrion.
Re-read Health data in the You tab reads the last 60 days from Apple Health again and replaces Metrion’s copy of those days. Your check-ins, goals, sleep answers and notes stay as they are, and Apple Health does not change.
Use Delete all data in Metrion’s settings to remove its stored profile, imported workout summaries, calculated training data, plans, and saved coach notes, and return to onboarding. Your original records in Apple Health remain untouched. If you set up Metrion again and allow Health access, the app can import that information again.
You can manage notification permission in iOS Settings and notification preferences in the app. Notification delivery is local; there is no Metrion push-notification server.
Deleting app data or removing the app does not cancel an App Store subscription. Manage or cancel that separately in your Apple account’s subscription settings.
Purchases and Apple services
Apple processes App Store purchases and payment details. Metrion reads the subscription entitlement and transaction information Apple makes available so it can enable purchased features and restore purchases. A local entitlement record helps those features work offline. We do not receive your card details or operate a separate billing database.
Apple’s processing of purchases, platform diagnostics you choose to share, and any TestFlight feedback is governed by Apple’s terms and privacy information. If you deliberately submit beta feedback or a crash report through an Apple testing service, that service may make the submitted information available to us.
Visiting metrion.fit
The website does not request Health access. Its demonstrations use sample data and authored responses. It has no advertising, tracking pixels, analytics SDK, or account system. Fonts, images, and interactive assets are served with the site. The site itself does not set tracking cookies or store an advertising identifier in your browser.
The TestFlight beta list
The beta is open to anyone through Apple’s public TestFlight link, so the sign-up form is gone and no new address goes on the list. The addresses already collected are still held, and still removable, until they are removed. The site carries one form now: the removal field on Your privacy choices.
- What we store. Your email address, lowercased, and the date it arrived. That is the whole record. No name, no browser information, and nothing joined to it from the app.
- Why. To send you an invitation to the TestFlight beta through Apple, and to tell you when the beta ends. The public link has replaced the invitation, so the list has no remaining use and we are closing it. It was never a newsletter, it was never used for advertising, and it was never shared or sold.
- Where. In our relay service’s own database, described above. No part of the app reads it, and it is never joined to an App Attest identifier or to any coaching request.
- Rate limits. To stop the removal field being abused, we count requests per hour against a one-way hash of the requesting network address. That count holds no email address, and it expires within hours.
- Removing it. Use Remove your email address, or email us. Removal takes the row out; it is not marked as unsubscribed and kept. The page answers the same sentence whether or not the address was on the list, so it cannot be used to find out who signed up.
- How long. We delete the whole list when the beta ends, or sooner on request. Because the list is closed, it only shrinks from here.
TestFlight itself is Apple’s service. Once you accept an invitation, Apple’s terms and privacy information govern the beta, any feedback you submit, and any crash reports Apple shares with us.
The site is delivered through QuantCDN. Loading a page necessarily sends technical information such as your IP address, requested URL, request time, browser information, and any referrer supplied by your browser to the delivery infrastructure. Technical logs may be processed to deliver content, diagnose faults, prevent abuse, and protect the service. This information is not connected to the health data stored in your app.
QuantCDN operates a distributed delivery network. Technical processing can occur outside your country depending on the delivery configuration and network route. See QuantCDN’s privacy policy for its handling of information, and contact us if you need details about our website’s delivery arrangements.
If you contact us
If you email us, we receive your email address and whatever you include, such as your name, message, or an attachment. We use that information to respond, investigate an issue, or handle a request. Please avoid sending health records or sensitive screenshots unless they are necessary for the issue you want help with.
Email and support providers process messages on our behalf, and their processing locations may be outside your country. We limit access to people and providers who need it for the request. We do not add you to a marketing list just because you contact us.
Retention and security
Metrion’s local training records remain on your device until you remove them. We cannot remotely access, export, correct, or delete those local records for you. Your device’s passcode, operating-system security, and backup settings also affect their protection.
We keep support correspondence and technical information only as long as reasonably needed for the purpose described above, resolving a dispute, or meeting a legal obligation. We use reasonable safeguards for information we handle, but no device or communication system can be guaranteed completely secure.
We may disclose information we actually hold if required by law or reasonably necessary to protect rights, security, or safety. This does not give us access to the Health information held on your device.
Access, correction, and privacy concerns
You can contact us using the details on this page to request access to, correction of, or deletion of personal information we hold about you, or to raise a privacy complaint. Depending on the law that applies, you may also have rights to restrict or object to processing, request portability, or withdraw consent. We may need enough information to verify your identity before acting on a request.
For local app information, use your profile controls, Apple Health permissions, and Delete all data. For information handled independently by Apple, contact Apple or use its account controls.
We will review privacy concerns and aim to respond within 30 days. If we need longer, we will explain why. If you are not satisfied, you can contact the privacy regulator where you live. In Australia, this is the Office of the Australian Information Commissioner.
Children and changes to this policy
Metrion is not marketed as a service for young children. A young person should use training guidance with appropriate adult support, and a parent or guardian must authorise use or purchases where the law requires it. We do not knowingly ask children to send us personal information. Contact us if you believe a child has sent information that should be removed.
If our data practices change, we will update this page and its effective date. Where required, we will provide a notice or seek permission before a new use of personal information. A new policy does not itself grant Metrion additional Health permissions.