LEGAL
Privacy Policy
Last updated: 13 July 2026
The short version: Ischys runs entirely on your device. It has no account, no server, and no analytics. It does not collect, transmit, sell, or share your data — because there is nowhere for it to send it.
Ischys is an on-device workout tracker for iPhone. This policy explains what the app does with your information. It applies to the Ischys app and this website (ischys.app).
What we collect
Nothing. Ischys has no backend, no user accounts, and no telemetry. Everything you enter — workouts, sets, weights, reps, notes, routines, and personal records — is stored in a database on your device only. We never receive it, and we have no ability to see it.
Apple Health (HealthKit)
If you choose to connect Apple Health, and only with your explicit permission, Ischys:
- Reads your heart rate while a workout is recording (for example, from an Apple Watch) to show your live heart rate during the session.
- Writes your finished workouts to Apple Health, so they appear alongside the rest of your activity.
This health and fitness data stays on your device and within Apple Health. Ischys does not transmit it off the device, does not share it with any third party, and does not use it for advertising, marketing, or data-mining of any kind. You can revoke Health access at any time in the iOS Settings app under Privacy & Security → Health.
Apple Watch
The optional Apple Watch companion mirrors and controls a live workout. It communicates only with the Ischys app on your paired iPhone over Apple's on-device connectivity. No workout data leaves your devices.
Where your data lives, and backups
Your training log is a local database on your iPhone. It is included in your device's normal backup (for example, iCloud Backup) if you have that enabled. Those backups are managed entirely by Apple under Apple's terms — Ischys has no access to them.
Exporting your data
You can export a full copy of your data as a JSON or CSV file at any time. Once you export or share a file, what happens to it is up to you; it leaves Ischys's control the moment you choose to send it somewhere.
Third parties and tracking
Ischys contains no analytics SDKs, no advertising, no trackers, and no third-party data collection. The bundled exercise catalogue comes from the public-domain free-exercise-db and ships inside the app; loading it involves no network request.
This website is a static page hosted on Cloudflare Pages. Cloudflare may process standard server logs (such as IP addresses) to deliver and protect the site, as described in Cloudflare's privacy policy. The site sets no cookies and runs no analytics.
Children
Ischys is not directed at children and collects no personal information from anyone, regardless of age.
Open source
Ischys is open source under the MIT licence. You don't have to take "nothing leaves your device" on faith — you can read exactly what the app does at github.com/ischys-app/Ischys.
Changes to this policy
If this policy changes, the "Last updated" date above will change with it, and the current version will always be at this URL.
Contact
Questions about privacy? Open an issue at github.com/ischys-app/Ischys/issues.