In iOS and in the latest Android version, there is always a persistent notification on the screen when apps access the microphone while running in the background. This makes perfect sense, since mobile users could be secretly eavesdropped on otherwise.
I am wondering whether apps that are active, i.e. in the foreground, are also required to visibly indicate when they are using the microphone. For example, the "rec" button in my recorder app turns red while it is recording. But could the app also use its mic permission and record audio without showing me any visible indication if it wanted to? Or is there anything in iOS or Android prohibiting this? I couldn't find anything in the documentation.
