The messages in German in the Fairphone Updater App are rather poorly translated, e.g. betreten is an irregular verb and experience translates to Erlebnis or Erfahrung depending on context.
“Klangverstörung” from the audio settings (roughly: sound irritation or sound derangement) was already mentioned here.
Fairphone doesn’t have a native speaker in their staff as it seems.
That’s not critical of course, but why don’t you just post the german messages here on the forum before including them in the software, to have it proof-read by the community? There are many Germans here. I can help too.