Using external microphone to disable internal mic(s)

I was not able to find out any information on this site but I have found other information on the web about how you could do this. Using a external microphone and only recording from the microphone you will need to have a TRRS microphone. This means that there is 4 sections to your audio jack (what is inserted into your audio jack on your iPad or iPhone). 3 lines and the tip make four sections. See Pic below. Using this jack (Top Left corner picture) will remove ambient noise from your recording (basically disabling your external microphones). Hope this helps some people. I have been using my iPad to record for 7+ years and only just found this in the last 6 mo.