Privacy Policy

This Privacy Policy explains how the Strathlon mobile application (the "App") handles your information. We have designed Strathlon to keep your data on your device wherever possible. The App works without an account or a login, and it is ad-free: the only analytics it sends go to Strathlon's own server (sections 5A and 6).

1. Who we are (Data Controller)

The data controller is Chanaka Ekanayake trading as Strathlon, developer of Strathlon. You can contact us about privacy at [email protected].

2. No account needed

Strathlon works without an account: you start using it straight away, without an email/password sign-up or a social login. The name you can enter during setup is optional; the App uses it to personalise what you see, includes it in your iCloud backup while that switch is on (section 7), and gives it to your AI coach so it can address you (section 5). Your subscription is identified to us only by the anonymous transaction identifier Apple assigns (see section 6). The one time we hold an email address is when you choose to give us one: sending a feature request (from the app, or from the form on this site), or, before 25 September 2026, joining our launch list (see section 14).

3. What we collect, and why

The following is created and stored on your device and leaves it only where this policy says so:

4. Apple Health (HealthKit)

With your permission, Strathlon reads data from Apple Health to personalise your plan and nutrition targets and to auto-fill your stats. Access is permission-based: Strathlon reads the figures you permit. With your permission, your iPhone saves the food you log in Strathlon to Apple Health as daily totals of calories, protein, carbs and fat, and keeps each day's entries in step when you change that day's food; if you use Strathlon on an Apple Watch, the watch app saves the workouts it records to Apple Health. Those are the only things Strathlon writes, and it changes or removes only the entries it saved itself. Food and workouts Strathlon saved to Apple Health stay in Apple's Health app when you clear your data in Strathlon or delete the App; you can delete them in the Health app. Health data goes to our AI provider, through our Worker, only when you switch on the AI coaching described below or one of the two separate cycle opt-ins in section 4A. Your latest weight, which may come from Apple Health, is part of the default-on iCloud backup to your own iCloud (section 7), and a workout route is used only on your phone (see the list below). The list below is a list of reads only: it sets out what the App asks permission to read from Apple Health; what Strathlon writes is described above. Specifically, the App requests read access to:

• Active and resting (basal) energy burned
• Heart rate, resting heart rate, walking heart rate average and heart-rate variability (HRV)
• The beat-to-beat heartbeat timings behind your Apple Watch's overnight HRV readings, from which your phone works out its own HRV figure
• Heart-rate recovery (Apple's one-minute recovery after a hard effort)
• Respiratory rate
• Blood oxygen (SpO2)
• Wrist temperature (overnight, while sleeping)
• Body temperature you log, for example from a thermometer
• Blood pressure (systolic and diastolic), from a cuff that saves to Apple Health or readings you add yourself
• VO₂ max
• Body weight, height, body-fat percentage and lean body mass
• Biological sex and date of birth (for accurate metabolic calculations)
• Steps, flights climbed, walking and running distance, cycling distance, swimming distance and exercise minutes
• Your Activity ring summaries (Move, Exercise and Stand, with your own goals)
• Mindful minutes
• Food calories (dietary energy) that other apps save to Apple Health; the food Strathlon saves there itself is left out of this read
• Workouts, and the route of a workout that has one. A route is read only to tell outings of the same length apart: Strathlon turns it into a few numbers on your phone, dropping the coordinates as it reads them, and the route itself stays in Apple Health
• Sleep analysis, including sleep stages (deep/REM/core/awake), sleep efficiency and bed/wake times
• Menstrual flow, only if you use the cycle-aware features in section 4A (asked for separately)

Optional: sharing Health data with the AI Coach. Your Apple Health data goes to our AI provider only with your permission: if you turn on "Share my health data with the AI coach" (off by default; offered once during onboarding and available any time in Settings → App settings → Privacy & your data), certain Health-derived figures may be sent to our AI provider (section 5) solely to generate your coaching and the AI Health Analyst's answers, and only when a feature you use needs them. These are: your weight and weight history, BMI and body composition (including body-fat %), your metabolic rate (BMR), your whole-day calorie burn split into its resting and active parts, heart rate and resting heart rate, overnight heart-rate variability (HRV; on nights with enough Apple Watch beat-to-beat timings, an HRV your phone works out from those timings), the heart-rate recovery measured between your sets and Apple's one-minute heart-rate recovery, your walking heart rate compared with your own usual, respiratory rate, blood oxygen (SpO2), overnight wrist temperature, cardio fitness (VO₂ max), your blood pressure as your own average over the last 30 days (or, with no reading in those 30 days, over the last 90) and over the 30 days before, with how many readings are behind each (an average over a single reading is that reading's value) and, when Apple Health shares readings only from a recent date, that date, a note when you logged a body temperature of 38 °C or above in the last 24 hours, with that temperature and the time you logged it, today's steps, flights climbed (today and over the last 7 days), walking and running distance and exercise minutes, your Apple Activity rings over the last 7 days (on how many days each ring was closed, your own Move, Exercise and Stand goals and your average stand hours), your mindful minutes and the number of sessions over the last 7 days, your recent workouts and the heart-rate shape of your most recent one (a dozen figures your phone works out from the readings), a summary of your activities from the last 28 days (for each kind: how many, the latest date, usual length, average heart rate and calories; your five most recent; and how your repeated activities compare with your own earlier ones, worked out on your phone), your sleep in detail (including the deep/REM/core/awake breakdown, broken nights, sleep efficiency, bed/wake times and sleep debt), the effort rating you give a session after it, and a derived "readiness" score. The same switch adds your calories burned, energy balance, heart rate and sleep to your written weekly review and to the Progress cards you ask the coach about. When your coach asks and you agree in the chat, it can also see older history of some of these figures (see section 5). Wherever your energy balance goes to the coach, a day with nothing logged in Strathlon counts the food calories another app saved to Apple Health, and the coach is told on how many days that happened. The list of your blood-pressure readings and when each was taken, the beat-to-beat timings and other apps' individual food entries are used only on your phone. If you have told the App you are on hormone therapy, including HRT for menopause (an optional question; see below), that status is also covered by this same switch and is shared only when it is on, so the coach reasons from your actual logged data. Everything this switch shares is used only to generate your coaching and the AI Health Analyst's answers, and you can turn it off at any time. Your reproductive/cycle information has its own separate controls, described in section 4A.

This same opt-in powers the AI Health Analyst, which lets you ask the coach plain-English questions about your Health data (for example your sleep, resting heart rate or recovery) and shows a "readiness" summary. It uses the figures listed above, and Strathlon keeps your cycle dates, flow and history on your device (see section 4A).

Biological sex and hormone therapy. Strathlon asks for your biological sex as a required setup field. It is a calculation input rather than a label: the metabolic-rate equations the App uses were derived separately for male and female bodies, and the App's minimum daily calorie floor is keyed to it. Like your age and height, it forms part of your basic profile and is included in the standard iCloud backup and in the context sent to the AI Coach, because the calorie model cannot be applied or explained without it. Strathlon separately asks an optional question about hormone therapy (testosterone, estrogen, HRT for menopause, or none / prefer not to say), asked of every user. Its only purpose is accuracy: for testosterone or estrogen, where no measured body-fat percentage or lean mass is available, it adjusts the App's estimate of your body composition, which changes your calorie targets; HRT for menopause uses the standard calorie estimate. It is treated as special-category health data: it is stored on your device, excluded from the iCloud backup unless you switch on the separate, off-by-default "Back up health & safety details", and shared with the AI Coach only under the "Share my health data with the AI coach" switch above. Setting it back to None in Settings → Body & stats deletes it everywhere the App holds it. It is used only in the ways this paragraph describes.

You can grant or revoke Health access at any time in iPhone Settings → Privacy & Security → Health → Strathlon. Declining only means you'll enter some values manually.

4A. Cycle data: what stays, and the two things that can leave

If you log your period in Apple Health, Strathlon can read it to add gentle, optional cycle-aware guidance. Cycle data is special-category data, so it is handled separately from everything in section 4, under its own switches in Settings → Cycle-aware insights. "Cycle-aware insights" itself is on unless you switch it off, and does nothing until you allow Strathlon to read menstrual flow from Apple Health; the two switches that can send anything are off by default. These switches are separate from the "Share my health data with the AI coach" switch. So that you can see exactly where the line falls:

Both switches are off by default and either can be turned off at any time.

5. AI processing (Anthropic & Cloudflare)

The AI Coach features (chat answers, AI meal plans, "describe-to-log", and photo calorie/macro analysis) are powered by a large language model. When you use these features, the App sends the relevant content to a Cloudflare Worker that we operate, which forwards it to Anthropic's Claude models to generate the response. What is sent depends on the feature and may include:

• The chat message or food description you type;
• A photo you give it: a meal, a nutrition label (sent on its own with a fixed instruction to read the figures), or a dumbbell, plate, machine display or logbook line when you tap Snap to fill in a workout (sent on its own with a fixed instruction to read the weight and reps). A meal photo also carries today's dish list, today's logged food and the last four exchanges of the chat;
• Your workout plan and training: your weekly schedule, today's session, the current week day by day with every set you logged, your phase and streak, and your training record;
• Your food and targets: today's and yesterday's meals, foods you repeat, your targets for every kind of day and any meal plan you have saved;
• What your coach remembers: your own notes from the "What your coach remembers" screen, what it has learned from your chats and what the App has noticed in your logs;
• The date, time and time zone on your phone;
• Your health & safety details: see the box below;
• Your Apple Health figures, only with the switch in section 4.
• Older history, only when your coach asks and you agree. When a question needs more than the recent figures above, your coach can ask for older food, training, health or body history, at most two years back. A card in the chat names exactly what and which dates; it is sent only when you tap Share, and Not now keeps it on your phone. After you tap Share, your phone works the figures out from your log and sends only them, for that question and the rest of that conversation: from your Strathlon food log, for all the days or only the days of one kind you or your coach name, such as training days or weekends, per day or as weekly or monthly averages, your calories, protein, carbohydrate and fat and how many days you logged (and, for each day, how many items) — and, when the coach asks for them, for days in the last 60, each item you logged by name with its meal, calories, protein, carbohydrate and fat, and how many times and on how many days you logged each; from your training log, per week or month, how many days you trained, how many of them completed everything prescribed, your sets and your training volume — and, for 31 days or fewer, each training day’s sets, volume and whether everything prescribed was done, with its exercises and each one’s heaviest set and number of sets — or one lift’s heaviest set per week or month; and, only with the switch in section 4 on, Apple Health figures per day (for 120 days or fewer) or per week or month — sleep, resting heart rate, heart-rate variability, VO₂ max, steps, active calories, one-minute heart-rate recovery, blood pressure (only as an average of 3 or more readings), weight, body-fat percentage and lean mass, the food calories other apps saved, and workouts recorded outside Strathlon. Each figure goes with how many days, nights, readings or weigh-ins are behind it. The figures are not saved in your conversation; your coach’s answer, which may quote them, is.

Meal plans and shopping lists. Your coach sees your name, age and goals, whether your calories are set at maintenance, your diet type, restrictions, cuisines, cooking time and low-carb substitutions, and any injuries, food allergies, supplements to avoid and health & safety notes, with that day type's calorie, protein, carb and fat targets and the calories each meal should carry (your weight only with health sharing on), to write a day's meal plan and the same to fill a plan's empty slots, with which slots are empty, what the meals already on it add up to and the calories, protein and carbs left for the new meals — only when you tap Generate or Regenerate on a meal plan. When you make a shopping list, the App sends the name and calories of any meal with no ingredients listed, with your diet preferences, allergies and health & safety notes, so the list can take them into account. Each is sent only when you tap, through our server to our AI processor, in the same way as a coach message.

We use the following processors for this feature:

• Cloudflare, Inc.: hosts the proxy ("Worker") that authenticates your subscription, counts your coach credits, applies fair-use limits, and routes the request. It passes your messages and photos on to Anthropic and keeps only the records described in section 6.
• Anthropic PBC: operates the Claude AI models that generate the response from the content sent.

These providers process your content to deliver the feature you requested. Under our API arrangement, your AI requests are excluded from model training. They carry the name you entered during setup, if you entered one, so your coach can address you by it.

Spoken coaching (optional, your own OpenAI key)

Strathlon can speak a set of short coaching cues out loud during a workout: "Paused.", "Resuming.", "Ten seconds. Get ready.", and so on. Generating that audio uses your own OpenAI API key and starts when you begin the one-time download, so OpenAI is contacted only after you have entered your key and started it.

• OpenAI, L.P.: turns the phrases into audio, if and only if you have set this up.

What is sent is our own fixed list of coaching phrases (the same list for every user, compiled into the app) together with your API key as the credential. Those two things are the whole request. The audio is then stored on your device, and a workout plays it from there.

5A. Other things the App sends

Product-update notifications (on unless you switch them off). So we can send you notices about new versions, the App registers with our Cloudflare Worker. It sends five things: the notification code Apple issues to Strathlon on your phone (this identifies that installation of Strathlon; it changes when you reinstall or restore), the word "ios", whether the App is a test or App Store build, your build number, and the kinds of notice you've asked for (currently only product updates). Our server keeps it on its own, under that notification code. The registration is repeated at most once a day when you open the App. Our server keeps the date it last heard from your phone (the day only) and deletes a registration it hasn't heard from for 90 days, or straight away when Apple says the code is no longer valid. Switch it off in Settings → App settings → Privacy & your data → Product updates.

Failure reports (on unless you switch them off). When a step of the App fails (reading Apple Health, the watch link, the subscription check, iCloud, notifications, downloaded content or spoken coaching), the App sends our Worker five things: which step, a short label for the operation, one word for the kind of failure, the time, and your build number. About once a day it also sends a record that reporting is working. Reports are batched on your phone and sent on a later launch. Those five things are the whole report. Our server also records the country the connection came from (a two-letter code) and deletes reports after 90 days. Switch it off in Settings → App settings → Privacy & your data → Help improve Strathlon by sharing failures.

Barcode lookup (Open Food Facts). When a food photo you take has a barcode in it, your phone reads the barcode number on the device and asks Open Food Facts, a free public food database run by a French non-profit, for that product's declared nutrition figures. Your phone contacts Open Food Facts directly, so it sees your device's internet address, as any website you visit does. The request carries only the barcode number and the App's name. Open Food Facts is not our processor and handles requests under its own policy.

Feedback and requests. What you send through Feedback & Requests goes to our Worker; section 14.2 describes it.

6. Subscriptions (Apple)

Strathlon's AI features require an auto-renewing subscription, purchased through Apple's App Store using Apple's StoreKit. Apple processes the payment. Your card and payment details stay with Apple.

To confirm you're entitled to the AI features, the App sends the Apple-signed subscription transaction (a cryptographic token) to our Cloudflare Worker, which verifies it directly with Apple's App Store Server API. The Worker keeps a record keyed to the anonymous Apple original transaction identifier in order to count your coach credits, apply fair-use limits and log anonymised AI usage and cost. For each AI request it records which AI feature the request was for (for a coach message, including whether it carried part of the app’s built-in guide or was a question about the app that matched none of it), the AI model used and the rule that chose it (for example that the message named a food, was a photo, or came from a Progress tile), token counts and estimated cost; what kind of request it was, worked out from its shape (a typed message, a photo, a label, a meal plan, your weekly review, or older history you agreed to share, with which kinds of history and how much); how many coach credits it used; the billing month it falls in, taken from Apple’s signed record of your subscription; its size, how many photos it carried, whether it was answered and the most it could have cost. Each request carries a random code the App makes for that message, the App’s own weighting of that kind of request and your phone’s time-zone offset, which sets when your day starts again, and the Worker keeps two scrambled fingerprints of the conversation, which cannot be turned back into your words and are erased after about two hours, so that an automatic follow-up counts with the message that caused it. From these records it keeps a running count of the coach credits you have used this billing month and today (by your phone’s local day) and the balance of any extra coach credits you have bought. None of this includes what you wrote. This identifier is a code Apple assigns to your subscription, separate from your name, email and Apple ID, and these records are kept under it alone.

Extra coach credits. When you buy a pack of extra coach credits, Apple processes the payment. The App then sends our Worker Apple’s signed record of that purchase as Apple issues it: it names the pack, its transaction number and purchase date, the App Store country and the price paid, and carries a code the App makes from your subscription’s identifier when you buy, so the purchase is added to your subscription. The Worker checks Apple’s signature, adds the credits once, and keeps which pack, how many credits, when, and the price and currency paid in a ledger against your subscription’s anonymous identifier, together with any refund Apple reports; a refunded pack’s credits are taken back from the extra credits you have left, never below zero. Apple also tells our server directly when a pack is bought or refunded. The ledger is what lets your extra credits follow you to every iPhone and survive a reinstall, lets a refunded pack’s credits be removed, and lets the App show you a list of your purchases. It holds no name, email address, Apple ID or payment details.

7. Where your data is stored

The large majority of your data (profile, food and training logs, progress, and in-app analytics) is stored on your device and is included in your normal device and iCloud device backups (which Apple controls, rather than us). What our servers hold is: the subscription and usage record described in section 6; the transient AI request content described in section 5; the notification registration and failure reports described in section 5A; the feedback and requests you send us (section 14.2); and, from this website, roadmap votes and visit counts (section 15).

Strathlon's own iCloud backup (your private iCloud account).

Separately from Apple's device backup, the App can copy some of your data to your own private iCloud account so it is restored if you reinstall or change phone. The backup goes only to your personal iCloud account; what your AI coach is sent comes from your device, as sections 4 and 5 describe. It is split across several switches in Settings → App settings → Privacy & your data:

Strathlon keeps your cycle dates, flow and history on your device, outside all of these. One cycle-derived detail is included in "Back up health & safety details" when that switch is on: whether you've told us you still menstruate. You can turn any switch off at any time; turning one off also removes that data from your iCloud backup.

8. Advertising and tracking

Strathlon is ad-free, and the only analytics the App sends go to Strathlon's own server (sections 5A and 6). We use your personal data only to run Strathlon for you, in the ways this policy sets out.

9. Retention

On-device data remains until you delete it, reset the App, or delete the App. The AI request content sent to our processors is used to generate your response and is subject to those providers' own limited operational retention (for example, short-term abuse-prevention retention); your conversation, and any photo you sent in it, is kept on your phone, and our server passes each message to the AI and keeps only the records described in section 6. The anonymised subscription/usage records, your coach-credit counts and the ledger of extra coach credits bought and refunded are retained for fair-use enforcement, accounting, refunds and fraud prevention. A notification registration is deleted once we haven't heard from your phone for 90 days, and failure reports are deleted after 90 days.

10. Legal basis (UK GDPR)

For users in the UK and EEA, we rely on the following legal bases under the UK GDPR / GDPR:

• Performance of a contract: to provide the App's features you request, including AI responses and subscription verification.
• Consent: for access to Apple Health data and your camera/photos, which you grant through the iOS permission prompts and can withdraw at any time.
• Legitimate interests: to keep the service secure, prevent abuse, and understand anonymised, aggregate AI usage and cost.
• Explicit consent (Article 9): some of what you may choose to enter is special-category data: health information (allergies, pregnancy or breastfeeding, chronic conditions, medications, injuries, cycle data, hormone-therapy status) and, where a dietary preference such as halal or kosher reflects a religious belief, that preference. Every one of these fields is optional and is entered by you; you provide explicit consent by entering it, and you can remove it at any time in the App. We use it only to make the App's plans and coaching safe and appropriate for you.

11. Your rights

Because Strathlon works without an account, most of your data is in your own hands: you can view, edit, or delete it directly in the App, and deleting the App removes the on-device data. Where we hold data (the subscription and usage record, the notification registration and failure reports in section 5A, and anything you send us in section 14), you have the right to request access, correction, or deletion, and to object to or restrict processing. Note that we may be unable to link a request to a specific record without the relevant Apple transaction identifier. To exercise your rights, contact [email protected]. You also have the right to lodge a complaint with the UK Information Commissioner's Office (ICO) or your local supervisory authority.

12. Children

Strathlon has a minimum age of 16, and we recommend it for ages 18 and over. Onboarding blocks anyone who indicates they are under 16, and for users aged 16 or 17 the App keeps calories at a healthy maintenance level or above. We do not knowingly collect data from anyone under 16. If you believe someone under 16 has used the App, please contact us so we can help.

13. Camera & photos

Strathlon asks for camera access so you can photograph your food, its packaging and nutrition label, gym equipment when you use Snap to fill, your progress photos, a meal in your meal plan, and your profile picture. When you choose an existing photo instead, Strathlon uses Apple's photo picker, which gives the App only the photo you pick, so camera access is the only photo permission it asks for. Food, label and equipment photos are sent to our AI processors (section 5) to read them; for a barcode, only the number goes to Open Food Facts (section 5A). A photo you send in the AI Coach chat is kept on your phone with the conversation, so you can ask again, and is removed when the conversation is cleared or you reset the App. Progress photos stay on your iPhone unless you switch on Sync progress photos to iCloud (section 7), and a meal or profile photo stays in the App.

14. Email addresses you give us

There are two, and only two, places where we hold an email address you chose to give us. They are stored separately, in different records, and are used for different things.

14.1 Launch notification list (closed)

Until 25 September 2026, you could register your interest on our website ("register your interest" / "Notify me"). For anyone who did, we store: your email address, the time you signed up, which page you signed up on, and the exact consent text you agreed to. We use this for a single purpose: to send you one email announcing Strathlon's launch on the App Store. That one email is the only use we make of it.

The lawful basis is your consent, which you can withdraw at any time. The list is deleted no later than 60 days after the App Store launch. To be removed sooner, use the unsubscribe link in any email we send, or contact [email protected].

14.2 Feature requests and bug reports (in the App, or on our website form)

When you send us a feature request or bug report, the email field is optional. You can submit without it. If you do give one, it is stored with that submission, alongside the request itself: what you wrote (its type, title and description), the time you sent it, and whether it came from the App or the website form. Submissions from the App also carry a short technical note (the App version and build, your iOS version and your device model) and a random per-install identifier generated on your device, used only to rate-limit and de-duplicate submissions. That identifier is not your name, your email or your Apple ID, and there is no account for it to be attached to.

We use the email address for one thing: to reply to you about that request. It stays with that submission. Our public roadmap lists only items we choose to publish, and shows only a title and a short summary for each.

The lawful basis is our legitimate interest in receiving, triaging and responding to product feedback. Unlike the launch list, feature requests have no automatic deletion schedule: we keep them while the request is still relevant to the product, so we can see what was asked for and why. To have your submission or your email address removed from it, contact [email protected].

15. Website cookies and visit measurement

Our website sets one cookie, and only if you vote on the public roadmap. It is described immediately below. It is the only cookie the site sets, and the App works without cookies.

The roadmap voting cookie (st_voter). The first time you vote on a feature request, we set a first-party cookie so that the next vote you cast is recognised as coming from the same browser. It contains only a randomly generated identifier, made when you first vote, and a signature proving we issued it. Its only purpose is to keep voting fair: one browser, one vote per item, without making you create an account.

It lasts one year, is marked HttpOnly so scripts on the page cannot read it, Secure so it is only ever sent over HTTPS, and SameSite=Lax so it is not sent from other websites. It is set only on strathlon.com and strathlon.ai, the two addresses of this website. Because it identifies a browser rather than a person, all it tells us is that two votes came from the same browser. It is set only when you vote; clearing your browser's cookies removes it, and your existing votes stay counted but your browser will be treated as new if you vote again. Our lawful basis is our legitimate interest in preventing repeat voting from distorting the roadmap.

Visit measurement, without cookies. On our website only (not in the App), we count arrivals so we can tell whether people are finding our guides. It runs on our own server, without cookies, and records four things. When a page loads, we record the page you arrived on, the time, the hostname of the site that linked you (for example "google.com" or "chatgpt.com"), and the country your request reached us from.

Those four things, with a category such as "search" worked out from the hostname, are the whole record. Of the referring page we keep only its bare hostname, because a full referring address can contain search terms and other personal details, and we record only the page you arrive on, so each visit is a single entry. The data is processed and stored by Cloudflare on our behalf. Our lawful basis is our legitimate interest in understanding how our website is found; the record is anonymous.

16. Changes to this policy

We may update this Privacy Policy from time to time. Material changes will be reflected by the "Last updated" date above and, where appropriate, highlighted in the App.

17. Contact

Questions about this policy or your data? Email [email protected].

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