KFA-RechnerPrivacy policy
Last updated: 8 November 2026. This is a translation for information. The German version is legally binding.
In short: The app processes your body data on your device. There is no server, no account, no advertising and no analytics. We never see your measurements. On iPhone the data may be part of your own iCloud or device backup. The app writes to Apple Health or Health Connect only with your permission and reads nothing from them.
Controller
LinguaFlow e.U., owner Christian Nouza
Linzer Straße 17, 4100 Ottensheim, Austria
Email: hello@linguaflow.app
The app
What is stored on your device
Sex, units, weight, height, neck, abdomen or waist and hip circumference, and the history of your circumferences with dates. This is used to calculate the result, to show your entries again the next time you open the app, and to show your history.
This data stays in the app's storage on your device until you change it or delete the app. Deleting the app removes it from your device. None of it is sent to us.
What is written to Apple Health and Health Connect
Only when you trigger a save and have agreed in your device's dialog does the app write these values to your health record:
| Value | iPhone (Apple Health) | Android (Health Connect) |
|---|---|---|
| Body fat percentage | yes | yes |
| Weight | yes | yes |
| Lean body mass | yes | yes |
| BMI | yes | no |
| Abdomen (men) or waist (women) circumference | yes | no |
Purpose: You keep your measurements in one place and can view them there alongside your other health data. That is the only purpose.
Health Connect in particular: On Android the app requests only the write permissions for weight, body fat and lean body mass. It reads no data from Health Connect. The weight written is the value you entered; body fat and lean body mass are the estimates calculated from it. This data is not sent to us or to third parties, not sold, and not used for advertising or to assess creditworthiness or insurability.
Withdrawing permission: You can withdraw permission at any time: on iPhone in the Health app under Profile, Apps, KFA-Rechner; on Android in Health Connect under app permissions. Values already written stay in your health record until you delete them there.
What the app does not do
- It does not read data from Apple Health or Health Connect.
- It does not send your body data to any server or third party.
- It contains no advertising, no analytics tools and no third-party crash reporting.
- It requires no account and makes no automated decisions about you.
What happens outside the app
Apple Health and Health Connect are part of your device, and Apple and Google are responsible for them. Values in your health record follow its own settings.
iPhone: The app's data may be part of your own iCloud or device backup if you have switched that on. That runs through your Apple account and we have no access to it.
Android: The app does not take part in Google Backup. Its stored measurements are not backed up and are gone after you change devices.
Legal basis
Body measurements and body fat percentage are health data. We do not receive them. Insofar as the GDPR applies to processing on your device, it is based on your explicit consent (Art. 6(1)(a) and Art. 9(2)(a) GDPR), given by entering the data and by granting permission in your device's dialog. You can withdraw it at any time with effect for the future (Art. 7(3) GDPR).
Buying the app
You buy the app in the App Store or on Google Play. Apple or Google handle the purchase and are responsible for it under their own privacy terms. They provide us with sales reports for our accounting, but never your body data. Apple and Google may collect their own diagnostics through their systems if you have allowed this on your device.
This website
This website uses no cookies, no tracking, and no fonts or scripts from other servers.
It is hosted by Cloudflare, Inc., 101 Townsend St., San Francisco, CA 94107, USA (Cloudflare Pages). When you open a page, Cloudflare processes technically necessary data such as IP address, time, requested address and browser details to deliver the page and protect it from abuse. The legal basis is our legitimate interest in a secure, working website (Art. 6(1)(f) GDPR). Data may be transferred to the USA. Cloudflare participates in the EU-U.S. Data Privacy Framework, on which the transfer is based (Art. 45 GDPR). See Cloudflare's privacy policy.
Contact by email
If you write to us, we process your address and message in order to reply (Art. 6(1)(b) and (f) GDPR). Our email runs on Google Workspace. We keep messages as long as needed to deal with them or as required by statutory retention duties. Please do not send us your body measurements; we do not need them for support.
Your rights
Under the GDPR you have the right of access (Art. 15), rectification (Art. 16), erasure (Art. 17), restriction of processing (Art. 18), data portability (Art. 20) and objection (Art. 21), and the right to withdraw consent at any time (Art. 7(3)).
Because your body data stays with you, on your device and where applicable in your own backup, you can view, change and delete it there yourself. We hold no copy and so cannot hand it over. For anything else, such as emails to us, write to hello@linguaflow.app.
You can also lodge a complaint with the supervisory authority:
Österreichische Datenschutzbehörde
Barichgasse 40–42, 1030 Wien, Austria
E-Mail: dsb@dsb.gv.at, Telefon: +43 1 52 152-0
www.dsb.gv.at