Privacy Policy

Last updated: October 25, 2026

MachXDynamics is a flow simulation for iPhone. It runs entirely on your device. It has no account, no server, no analytics and no advertising. This page explains what that means in practice.

This policy covers two things: the MachXDynamics app, and this website (machxdynamics.com). They are handled separately below.

The app

What the app collects

Nothing.

The simulation is computed on your device. The app makes no network connections of its own, has no sign-in, and contains no analytics, tracking, advertising or third-party SDKs. Your settings and slider positions never leave your device. We never see your name, email address, IP address or any identifier we could tie to you. iOS may contact Apple's App Store to confirm how the app was installed; this is handled by Apple and sends nothing to us.

What the app stores on your device

The app keeps a few small values on your device using iOS's standard app storage (UserDefaults): for example, whether you have seen the first-launch hint, and a one-time measurement of how fast the simulation runs on your iPhone. These values stay on your device and are deleted when you delete the app. They are included in your own iCloud or device backup only if you have turned that on for your device; that backup is held by Apple, not by us.

Crash reports

The app itself sends no crash reports or diagnostics. If you have chosen in iOS to share analytics with app developers (Settings › Privacy & Security › Analytics & Improvements), Apple — not the app — collects crash logs under Apple's own privacy policy and may make anonymous crash statistics available to us. They contain nothing we can link to you, and we use them only to fix bugs. You can turn this off at any time in the iOS setting above.

Downloads and purchases

Downloads and any purchases go through Apple's App Store. Apple processes them independently of us, under Apple's Privacy Policy. We see only aggregated, anonymous figures in App Store Connect. We never see who you are or how you paid.

Children

MachXDynamics is rated 4+. Because the app collects no data, it collects no data from children either.

This website

This website has no cookies, no analytics, no tracking pixels and no embedded content from third parties. The site uses your device's built-in fonts; nothing is loaded from a third-party font service.

The site is hosted on GitHub Pages, a service provided by GitHub B.V., Prins Bernhardplein 200, 1097 JB Amsterdam, Netherlands, and GitHub, Inc., 88 Colin P. Kelly Jr. St., San Francisco, CA 94107, USA. When you visit, the host's servers automatically process technical data your browser sends, such as your IP address, the date and time of the request, the page requested and your browser type, in server log files. This is necessary to deliver the site and keep it secure. The legal basis is Art. 6(1)(f) GDPR; our legitimate interest is the secure and reliable operation of the website.

GitHub may process this data in the United States. GitHub is certified under the EU–US Data Privacy Framework, which the European Commission recognises as providing an adequate level of protection (Art. 45 GDPR). How long GitHub keeps these logs is governed by GitHub's Privacy Statement; we have no access to them.

If you email us, we use your message and address only to answer you, and delete the correspondence when it is no longer needed for that purpose, unless statutory retention periods apply. The legal basis is Art. 6(1)(b) or (f) GDPR.

Your rights under the GDPR

The app collects no personal data, so there is nothing for the usual rights to act on. For the limited data described under "This website" and for emails you send us, you have the right of access, rectification, erasure, restriction of processing, data portability and objection (Art. 15–21 GDPR). To use them, write to the contact address below.

You also have the right to lodge a complaint with a data protection supervisory authority, in particular in the EU member state where you live.

Changes to this policy

If a future version of the app handles personal data in any way, this policy will be updated before that version is released. The date at the top of this page always shows the current version.

Controller

The controller within the meaning of Art. 4(7) GDPR is:

Dr.-Ing. Jürgen Grönner
Randebrockstr. 7a
46236 Bottrop
Germany

Email: legal@machxdynamics.com

We answer in English and German.