The android app asks for microphone privilege as of a few years back when they introduced the listen-in feature. The problem here to me, is that when they add the voluntary feature they force everyone to give the app all the permissions needed as well. By doing this your phone has no way of stopping the app from misbehaving as it has given permission for it to do so.

At least that was the case when the feature came out. I think I read something about android now letting you filter permissions and not blindly accept all that an app asks for?