Sollte euch die App grundsätzlich interessieren, dann installiert diese und exportiert direkt zwei PDF-Dateien, in der dann auftauchenden Kauf-Abfrage könnt ihr die Applikation dann für 0 Euro zur Vollversion aufwerten.

Hi! I’m the developer of the app. Thanks for the article! Sorry, my german is not the best, so i will make an english comment if you don’t mind.
So the app was previously a simple paid app, but now i changed it to free app with an in-app purchase. I tried to migrate my existing users to the new free app, so they don’t have to pay for the app again, but sadly the code i used does not work in the production version of the app. So to avoid negative feedback, i changed the in-app purchase price to free, until i can fix the issue. I submitted version 2.2.1 today which hopefully works(its just really hard to test this feature sadly). To answer a few questions:
„Why is the app not in german?“
Just to note, you can generate a report in German language. To translate the app, it would generate so much complexity: every time i update something, i would need to update all languages, create german screenshots, app description, changelog etc… so lots of extra work, and this is just a hobby project at the moment, i don’t have the resources to do this, sorry.
„With my health data in particular, I wouldn’t trust an app just because it’s free.“
The app is completely offline, i don’t have access to your data, so its safe to use. I don’t even have any third party tracking or analytics installed, just to avoid any potential issues. This makes things a bit difficult(for example to run an ad campaing or crash analysis), but this is something i want to keep in the future, a completely offline app.
„Will it support EKG?“
Yes, i’m working on this. So it will have a feature to export your EKG results with a better format that Apple provides, with more data. Its as bit tricky, since i only have access to the raw values, so i need to generate the same „graph“ first. But i’m on it
„Why i need to give write access?“
The report generation works fine without write access. If you go into the app settings, you can enter your blood pressure and blood sugar data manually, thats why my app requests these data. Many of my users use it without an Apple Watch, just to track blood pressure or blood sugar and this is a quick way to add these data. Its a bit more complicated to do in the Health app. (also, long press the app icon and theres an Add data button there to add it even easier/faster).
„For me, buying the 0 Euro Unlock does not work.“
Can you try to go into phone Settings / App Store and sign out. Then, start my app and try to purchase, it will ask you to sign in. Maybe this will solve the issue? This is really hard to debug as it works for most users and its not really my development. The issue might be related to being a free product, i’m not sure yet.
Let me know if you have any more questions!