How To Enable Stereo Recording On Tablets/smartphones Yielding Only Mono Albeit Having Two Internal Microphones?

So far, I thought it was a firmware error, but now I just found a 2nd device that has two internal microphone capsules but only yields a monophonic signal (1st one was the S2 Plus

Solution 1:

See what worked for me in the Motorola Moto G. I understand it is very dependent on the vendor/model, but I tried many combinations until I found that only with 48000 Hz I was getting stereo recording in that particular phone:

Recording stereo audio with a Motorola Moto G (or Moto X)