Setting/app to route audio input to phone's mic while a wired headset is connected to it I'm a new Android phone user. I'm looking for a setting or an application that can route audio input to phone's microphone while a wired headset is connected to it, but keep the audio output to the headset. I have been searching for this in Setting but I think it is not available there. I have been also searching for the app that can do this, the search results recommend me an app named SoundAbout, but it doesn't do what I want, it's just routing audio output to phone's speaker while a wired headset is connected to it.

So is there any?
There is no system-wide setting for this, unfortunately. And apps that try to control audio routing are usually hacks that cause problems on their own.

But I have a hardware solution for you -- buy one of those splitter adaptors that convert 4-pin TRRS into 2 3-pin TRS, separating for headphones and microphone, and only plug the headphones jack into your phone. Look for something like this: https://www.amazon.com/StarTech-MUYHSFMM-Headset-Splitter-Adapter/dp/B0058DOWH6 (I'm not recommending this particular adapter, just showing how it should look like).