When you say generally no, are there exceptions? For instance, is there an exception for certain Apple apps? I wonder, if there’s a special exception that most programmers don’t know about but Apple’s engineers and some hackers do, and a mainstream iOS app is designed by people with malicious intentions, could there be a risk that such an exception, amounting to an audio backdoor, would be exploited by such a mainstream app in order to record phone calls?

Can it continue recording even while another app that is in the foreground is using the microphone? For example, suppose the user is on a phone call using Signal, can SoundHound which was last run a week ago and is backgrounded record the Signal phone call?