@Christian Andreas Mielke , In fact, for personal devices, Intune never collects information on applications that are unmanaged. On corporate devices, any app whether it is a managed app or not is collected for Intune discovered apps report. Here is a table list the apps are monitored in discovered apps report:
https://learn.microsoft.com/en-us/mem/intune/apps/app-discovered-apps#details-of-discovered-apps
Hope it can help.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.