I've used the audio recorder. Other than the permission to use the microphone, it doesn't use any other permission. It doesn't even ask for general filesystem permissions, and assumes you are savvy enough to know how to use the standard Share functionality to get the files where you want.

The app does exactly what it says (records audio) and doesn't phone home, try to integrate with any services, collect any information about you. It just works.

If that type of thing is important to you, and you have a need for the functionality provided by one of the tools, there's your use case.