The worst part is that on iOS you can't just start and stop input stream separately from output, but you have to stop the entire audio session and restart it in

The worst part is that on iOS you can't just start and stop input stream separately from output, but you have to stop the entire audio session and restart it in output only category. You can configure the session to ignore all input channels, but that won't get rid of the mic indicator (or at least didn't back when the mic indicator was introduced in the first place). Yes, I work on an app that keeps the mic running all the time because of the above, and because ASIO doesn't allow disabling input at all.