Privacy policy
Last updated: 5 November 2026
Treadlink works without an account and has no ads, no analytics and no tracking. Your walks stay on your devices and in your own Apple Health, Health Connect and iCloud. We only receive what you choose to send us: feedback, a treadmill report, your answer to “How did it work?”, or your email for the beta waitlist.
Who is responsible
kalle.tech UG (haftungsbeschränkt)
Michaelkirchstraße 13
10179 Berlin
Germany
Email: [email protected]
See the imprint for more details.
In the app, on your devices
- Walks: time, speed, distance, steps, incline, heart rate and energy are stored on your phone. Your treadmills and settings are stored there too.
- Apple Health (iPhone, Apple Watch): with your permission, Treadlink reads heart rate, weight, height, date of birth and sex to estimate energy and steps, and the distance and energy of its own workouts. It saves your walks as workouts with steps, distance, energy, heart rate and effort.
- Health Connect (Android): with your permission, Treadlink reads heart rate and weight, and saves your walks as exercise sessions with steps, distance, speed, energy, climb and heart rate.
- Data from Apple Health and Health Connect is used only inside the app on your device. It is never sent to us, never used for advertising and never sold.
- iCloud (iPhone): if you turn on iCloud sync, your walks, treadmills and settings are stored in your own private iCloud database so your devices stay in sync. Apple stores it; only you can read it, we can’t.
- Apple Watch: the watch app measures heart rate during a walk and sends it to your iPhone.
- Bluetooth is used to talk to your treadmill and to heart rate monitors.
- Motion data is used to count steps when your treadmill doesn’t.
- Notifications such as care reminders are scheduled on your device.
Deleting the app deletes this data from your phone. Walks already saved to Apple Health or Health Connect stay there until you delete them in that app. You can delete iCloud data in your device’s iCloud settings.
What reaches us
Feedback and treadmill reports
When you send feedback or a report about a treadmill Treadlink doesn’t know yet, the app shows what will be sent before you tap Send. That is your message, the app version, your phone’s operating system and the app language, and, if you add them, the treadmill’s Bluetooth data and diagnostics. On iPhone the report is saved to the public iCloud database of the app, run by Apple; Apple assigns it an anonymous ID and gives us no name or email address. Without iCloud, or on Android, the app opens an email to us instead, which you send yourself.
We use reports only to answer you, fix problems and add support for treadmills, and delete them when they are no longer needed for that. Legal basis: Art. 6 (1) (b) and (f) GDPR.
“How did it work?”
After a walk on a treadmill model that isn’t confirmed yet, Treadlink may ask how well it worked. If you answer, the app sends to our server at api.treadlink.app: the treadmill model and its Bluetooth device information, the walk’s length, distance and steps, your rating, what worked, your note if you write one, the app version, the platform and the app language. Nothing is sent if you skip the question.
To keep fake reports out without an account, the app registers once with a random installation ID and proves it is the genuine app: on iPhone with Apple’s App Attest, on Android with Google Play Integrity, which Google checks for us. The installation ID is not linked to you. Your IP address is used briefly to limit the number of requests and is not stored with the report. We use these reports to mark treadmill models as confirmed for everyone. Legal basis: Art. 6 (1) (f) GDPR; our legitimate interest is reliable treadmill support and preventing abuse.
Beta waitlist
If you join the waitlist on treadlink.app, we store your email address, your phone platform, the page language and the time on our server. We use them only to invite you to the beta through TestFlight (Apple) or Google Play testing, which then send you their own invitation. We delete your address when the beta ends, or earlier if you ask us. Legal basis: Art. 6 (1) (b) GDPR, because you asked to be invited.
To keep bots out, the form uses Cloudflare Turnstile. It loads only once you start filling in the form, and Cloudflare then processes technical data such as your IP address and browser details to tell people from bots. It sets no tracking cookies. Legal basis: Art. 6 (1) (f) GDPR; our legitimate interest is a waitlist free of spam.
If you email us, we use your address and message to answer you (Art. 6 (1) (b) and (f) GDPR) and delete them when the conversation is over, unless the law requires us to keep them.
This website
This website sets no cookies and uses no analytics. It loads nothing from other providers, except Cloudflare Turnstile once you use the waitlist form; its fonts are served from our own server. When you visit it, your browser sends technical data such as your IP address, the time, the page and your browser’s name. Our server and Cloudflare use it only to deliver the page and protect it from attacks (Art. 6 (1) (f) GDPR); our server keeps no access logs.
Service providers
- Hetzner Online GmbH, Gunzenhausen, Germany: hosts our server and this website in Germany, under a data processing agreement.
- Cloudflare, Inc., USA: delivers this website and our server, protects them from attacks and runs Turnstile for the waitlist form, under a data processing agreement. Cloudflare is certified under the EU-US Data Privacy Framework.
- Apple (iCloud, App Attest) and Google (Play Integrity) as described above. Both are certified under the EU-US Data Privacy Framework.
When you download Treadlink, the App Store or Google Play processes data under their own privacy policies.
Your rights
You have the right to access (Art. 15 GDPR), rectification (Art. 16), erasure (Art. 17), restriction of processing (Art. 18), data portability (Art. 20) and to object to processing based on legitimate interests (Art. 21). Write to [email protected]. Because we don’t know who sent an anonymous report, tell us what you sent and when, so we can find it.
You can also complain to a data protection authority, for example ours: Berliner Beauftragte für Datenschutz und Informationsfreiheit, Alt-Moabit 59–61, 10555 Berlin.
Changes
We update this policy when Treadlink changes. The date at the top shows the current version.