Use android phone mic when connected bluetooth handsfree Android car unit

Hi, I purchased the app pro, but I finally request a refund because there's no documentation!

Simple question:

My android car stereo unit have bad quality microphone. And when I connect my android phone bluetooth handsfree, it disable the phone mic to use microphone on car unit.

I just want to still use phone mic when I'm connected to the car.

Is it possible? Whit paid version? How?

Thanks (French Canadian user!)

I know that you work hard on this app. It may seem simple to you, how your app work, but for a user it's very confusing.

I know that it's only 4$ for the app, but I can't understand how it's work.

Did you ever considering make an instruction manual?

Now no response on this board, I feel that I paid for nothing, no help, it's bad. I hope you will fix that.

Eric french Canadian user...