Privacy Policy

MassAI (“we”, “our”, “the app”) is operated from the United Kingdom. We take a minimal-data approach: we only store what the product needs to function as your AI personal trainer.

MassAI is an AI-powered app. The coaching, chat (including any voice notes you dictate), workout and recovery plans, nutrition insights and recipe suggestions, and photo analysis you see are generated by third-party artificial-intelligence models (currently OpenAI's) that process the inputs you give us; they are not produced by a human. Sections 4 and 5 explain exactly what is sent to our AI provider and how it is handled.

1. Who we are & how to contact us

For privacy questions, data export requests, or account deletion, email support@massai.fit.

2. What we collect

The only data we store on our servers is data you give us or data your device sends us:

• Account: email, sign-in provider identifier (Apple / Google).
• Profile: display name, height, weight, training goal, split and training-style preferences, experience level, daily activity level and step goal. Anything you enter in Settings or onboarding.
• Training data: workout sessions, sets, exercise preferences.
• Nutrition: meals you log (food name, macros, time), water intake, daily totals, and any recipes you save to your library.
• Health metrics (opt-in): HRV, resting heart rate, steps, and active calories, synced automatically from Apple Health (iOS only). Sleep hours can also come from Apple Health, or be entered manually by anyone without a compatible wearable, on iOS or Android. We do not use this Apple Health data for advertising or marketing, do not use it for any purpose unrelated to your coaching, and never sell or share it with data brokers.
• AI usage: a row per AI request (timestamp, route, and token/cost counters, no contents) for rate-limiting, cost control, and abuse prevention.
• Photo safety log: if a physique or food photo you upload is rejected by our automated safety check, we store a short text note describing why and a category label (e.g. “intimate”, “not a physique photo”), linked to your account, so we can review and act on abuse. We never store the photo itself, only the text note.
• Coaching history: the AI recommendations we generate for you (training plans, recovery adjustments, debrief suggestions, nutrition tips), the inputs they were based on (your training/recovery/nutrition state at the time, never photos), and whether you accepted them, plus body metrics derived from AI analysis (e.g. estimated body-fat range, never the photo itself). We use this to improve YOUR coaching. It is never used to train models or analysed across users unless you separately opt in to research use (off by default).
• Coach chat & memory: your conversations with the AI coach, across every chat you start, are saved only on your device, not on our servers, so you can revisit or delete any of them any time from the app; they're also cleared automatically if you sign out, delete your account, or revoke access. To keep the coach's memory of you without keeping a full transcript, it maintains a short rolling summary of recent context (roughly 150 words) and a small list of structured facts (for example “trains at home”, “left shoulder gets sore on overhead press”), both linked to your account. You can ask the coach to update or forget a fact, or email us to have your coach memory cleared.
• Feedback: if you send us feedback from Settings, we store your message, the category you picked (bug / feature request / other), and basic app info (app version, build number, platform) so reports are actionable. Submissions are write-only from your device, you can't read past submissions back in the app, and we never send the message text to our analytics provider, only the category.
• Subscription status: your plan (Free / MassAI Coach), billing period, and the subscription identifiers needed to keep your access in sync. Payment is handled entirely by Apple; we never see or store your card details.

3. What we do NOT store

• Your photos. When you upload a physique photo for the planner, or a food photo for nutrition logging, the image is sent to our AI provider for that single analysis call and then discarded. It is never written to our database and never uploaded to file storage. (If a physique photo fails the automated safety check, we keep only a short text note about why, never the image; see section 2.)
• Your voice recordings. If you dictate a message to the AI coach, the audio clip is sent to our AI provider to be transcribed to text for that single request, then discarded. It is never written to our database or uploaded to file storage.
• Camera footage from barcode scanning: frames are processed on your device only.
• Location.
• Advertising identifiers.

4. How we use your data

• To run the app: dashboard, logging, recovery score, AI coaching.
• To make the AI coach contextually aware (recent training, recovery, nutrition) and to remember useful facts about you across conversations.
• To transcribe voice notes you dictate to the AI coach into text.
• Per-user rate limits on AI calls (preventing abuse and runaway costs).
• To automatically screen uploaded physique photos for harmful, illegal, or non-compliant content before our AI analyses them, and to act on abuse (including suspending AI access or, where required, reporting illegal content).
• On-device reminders and coaching notifications, if you opt in (scheduled locally on your device; no data leaves your phone to send them).
• To show an at-a-glance snapshot (for example your recovery score, today's targets, or a running rest timer) on your Home Screen or Lock Screen if you add the MassAI widget or start a Live Activity. This uses only data already on your device, visible without unlocking your phone, and sends nothing new to our servers.
• To build your coach model: a small set of statistics computed from your own logs (for example how many days a week you actually train, your measured maintenance calories from your food logs and weigh-ins, how quickly each muscle group progresses, which coaching suggestions you accept, and your typical sleep). The coach uses these to tailor your plans, targets, and advice. This is arithmetic over data you have already given us, computed on our servers; no extra data is collected for it. You can see every measurement (with the evidence behind it) on the Coach model screen, reset any of them, or switch adaptive coaching off entirely, in which case the coach uses the same standard defaults for everyone. Every adjusted plan, target, or recommendation remains a suggestion you can accept, edit, or reject; nothing about your subscription or access is ever decided by the model.
• To process subscriptions and unlock the paid features you purchase.

We do NOT sell your data, share it with advertisers, or share it with data brokers.

5. Third-party processors

• Supabase (database, authentication, Edge Functions): stores your account, profile, training, and feedback data. EU-hosted.
• OpenAI (AI provider): powers every AI feature in MassAI: the AI coach and chat (including transcribing any voice notes you dictate), workout and recovery planning, nutrition insights and recipe suggestions, and both the analysis and the automated safety screening of any physique or food photo you upload. When you use these features, OpenAI receives your prompts, a snapshot of the relevant training, recovery, and nutrition state, and (for the photo and voice features) the image or audio itself. Per OpenAI's API terms, inputs may be retained by OpenAI for up to 30 days for abuse monitoring and are not used to train their models. OpenAI is based in the United States; transfers to them are made subject to OpenAI's standard contractual safeguards for international data transfers under their Data Processing Addendum.
• Apple & Google: only if you choose to sign in with them, in which case they verify your identity to us.
• Apple (App Store): processes your subscription payment. Apple handles your payment details; we receive only confirmation of your subscription status, never your card information.
• RevenueCat: our subscription-management provider. It receives your account identifier and purchase events from the App Store so we can unlock and keep your plan in sync.
• Sentry: crash and error monitoring, so we can find and fix bugs. It receives technical diagnostics (error messages, device/OS type), not your training or nutrition content, and crash reports are not linked to your account or identity.
• PostHog (product analytics, EU-hosted): anonymous usage diagnostics so we can see which features are used and where people drop off. It receives screen views and a few funnel events (for example, onboarding and paywall steps), not linked to your identity. No email or personal details, no session recording, and no cross-app tracking.
• USDA FoodData Central & the UK Composition of Foods Integrated Dataset (CoFID): public food databases we use for nutrition data, queried through our own servers. We send only the search term or barcode, never personal data. CoFID is © Crown copyright, used under the Open Government Licence v3.0; USDA FoodData Central is in the US public domain.
• Open Food Facts: another public food database we use for nutrition data. Unlike the sources above, food searches and barcode scans against Open Food Facts are sent directly from your device rather than through our servers, so your device's IP address is visible to Open Food Facts for that request, alongside the search term or barcode. No other personal data is sent. Open Food Facts data is used under the Open Database Licence (ODbL).
• Sentry, RevenueCat, Apple, and Google are also based in the United States; like OpenAI, transfers to them are made subject to standard contractual safeguards for international data transfers.

6. Legal basis (UK GDPR)

• Contract: account, profile, training data, and the AI features that run the service, processed to deliver it to you.
• Consent: Apple Health and push notifications are opt-in and revocable in iOS settings.
• Explicit consent for special-category data (Article 9(2)(a)): health metrics from Apple Health, and any health-related information you choose to share with the coach (for example an injury note it remembers), are processed only with your explicit consent, given when you enable Apple Health sync or when you share that information with the coach, and revocable at any time by disabling sync, asking the coach to forget a fact, or deleting your account.
• Legitimate interest: preventing abuse (AI rate-limit logs, automated photo safety screening) and keeping the app reliable and improving it (crash diagnostics via Sentry, anonymous product analytics via PostHog).

7. How long we keep your data

Account, profile, training, nutrition, saved recipes, feedback, and coach-memory data are kept while your account exists. AI usage logs are kept for 90 days. Photo safety notes (the text described in section 2) are kept while your account exists so we can address repeat abuse, and are deleted when you delete your account. When you delete your account, all of your personal data is erased immediately and permanently; there is no grace period, and deletion cannot be undone. Any residual copies in our encrypted database backups are purged within 30 days.

8. Your rights

Under UK GDPR you have the right to:

• Access a copy of the data we hold about you.
• Correct anything that's wrong.
• Delete your account and all associated data.
• Restrict how we use your data in certain circumstances.
• Receive a portable copy of the data you gave us, in a machine-readable format.
• Object to processing or withdraw consent at any time.
• Lodge a complaint with the Information Commissioner's Office (ICO) at ico.org.uk.

MassAI's AI recommendations are advisory suggestions you choose whether to act on. We do not make solely-automated decisions about you that produce legal or similarly significant effects.

Email support@massai.fit to exercise any of these rights.

9. Security

All traffic is encrypted in transit. Your password is never stored; we use sign-in providers. Database access is governed by row-level security so your records are isolated from other users at the database layer.

10. Children

MassAI is not directed at children under 16. If you believe a child has signed up, contact us and we'll delete the account.

11. Changes to this policy

If we make material changes, we'll update the “last updated” date and notify signed-in users by email or in-app notice.