Ὠκεανός
The river at the rim of the shield. Nothing crosses it.
Privacy policy
Your body's raw data stays on your phone. That is the edge of the world.
Homer rims the shield with Ocean, the river that bounds everything. Achilles has the same boundary: heart-rate variability, resting heart rate, sleep stages, temperature, and cycle logs are read from Apple Health on the device and never uploaded. The server sees a small daily summary and the workouts you log. Health data is never sold or shared with third parties.
Effective October 12, 2026 · Achilles
This policy explains what Achilles collects, why, where it goes, and how to delete it. It is written to be read. Where it names a company, it is because your data is processed there.
1. What stays on your phone+
Achilles reads Apple Health (HealthKit) with your permission: heart-rate variability, resting heart rate, sleep and sleep stages, steps, active energy, workouts, dietary intake, and, if you enable cycle tracking, menstrual flow and nightly wrist or basal temperature. Raw samples are never uploaded. Reproductive-health permission is requested separately and only when you turn cycle tracking on.
Cycle predictions are computed on the device. Meals you log are written back to Apple Health, tagged so Achilles can remove them if you delete the meal.
2. What we store on our servers+
Account. Sign in with Apple gives us a stable anonymous identifier and, if you share it, your email. Profile facts you enter: sex, height, weight, timezone, disciplines, baselines, goals, availability, and whether Goggins mode is on.
A daily snapshot. One row per day with derived numbers: HRV, resting HR, sleep duration and quality, steps, active energy, dietary totals, and the readiness score computed from them. If cycle tracking is on, the snapshot also carries your current phase and cycle day, and nothing else about your cycle. Turning cycle tracking off wipes those fields in the same transaction.
What you log. Workouts and their actuals, effort ratings, GPS-derived splits (not the route), meals and ingredients, fasts, supplements and whether you took them, peptide injections (dose, site, time), intentions, patterns you are cutting back on and the events and urges you record, and the goals you write.
Progress photos. Stored in a private per-user bucket on Amazon S3, served through short-lived signed links, kept until you delete them. You can delete a set or everything at any time from the app.
3. Who processes it, and why+
Anthropic (Claude). AI features send a deterministic summary of your day, relevant history, and your question or request to Anthropic's API to produce a workout, a meal estimate, the Daily Pulse, an answer in Ask Achilles, intentions, a pattern plan, or photo feedback. Progress-photo feedback sends the photos themselves. Anthropic processes this data to return a response and does not use API inputs to train its models.
Amazon Web Services. Our API and database hosting, photo storage, and Rekognition, which screens each progress photo for explicit content and confirms a person is in frame before it is stored.
Open Food Facts. Barcodes you scan are looked up against this public database. The barcode is sent; nothing about you is.
Apple. Sign in with Apple and App Store subscriptions. Apple tells us whether your subscription is active. We never see your payment details.
Google AdMob (free tier only). Shows ads in the free version. The ad SDK is never initialised for Pro accounts and never receives health, nutrition, cycle, pattern, or photo data. Ads are never shown on quit or urge screens, live trackers, the camera, or onboarding, and alcohol, gambling, and weight-loss ad categories are blocked.
4. What we never do+
We never sell your data. We never share health data with third parties for their own purposes.
We never upload raw HealthKit samples, period dates, flow logs, or temperature readings.
We never use your data to train AI models, and our processors are bound not to.
We never show ads next to health data, and we never let an ad network know your readiness, your cycle, or what you are cutting back on.
5. Your controls+
Revoke any Apple Health permission in the Health app at any time; Achilles keeps working with what remains.
Delete any workout, meal, fast, log, pattern, or photo set from the app. Deletion is immediate on our servers; backups age out within 30 days.
Disable cycle tracking to wipe derived cycle fields from the server in the same transaction.
Delete your account from Settings to remove everything we hold, including photos. Export is available on request.
6. Retention, security, children+
Data is kept while your account exists. Access tokens are short-lived and refresh tokens rotate. Photos and the database are encrypted at rest.
Achilles is for adults. We do not knowingly collect data from anyone under 18, and the app's peptide, supplement, fasting, and cessation content is written for adults.
7. Changes and contact+
We will post changes here with a new effective date, and tell you in the app when they matter. Questions: privacy@achilles.fitness.