Ios14

You have it right. The orange dot indicates that the microphone is in use by an app. In your example it is the microphone in use by the Phone app. BTW - there is also another green dot that may appear and that indicates that the camera is in use by an app. That is all there is to it. It is an awareness feature to keep you informed.

Axel F.

Tina67B wrote:

Is it just because the phone is in use? Just making sure no apps are recording.

Yes, no recording is in progress. Status icons and symbols on your iPhone - Apple Support states:

"An orange indicator  means the microphone is being used by an app on your iPhone."

When you are on a phone call, the microphone is required and being used.