Serial ports permissions in android

Hi.

Im making app in unity for android, which will be reading from serial com port... At this time i cant try it on prototype so im preparing. So i made simple script which will start and list all available.

  void Start()
     {
         string[] s = SerialPort.GetPortNames();
 
         for (int i = 0; i < s.Length; i++)
         {
             portList.text += s[i] + "\n";
         }
 
     }

But i when i run script on my test tablet nothing happens. After looking at logs through Android Monitor from android SDK, i can see unity throwing UnauthorizedAccessException: Access to the path "/dev" denied. I looked it up and there is nothing about this at all. So Im guessing that either im doing something wrong or i need rooted tablet...

So i know how to work with com ports... i just need access to them on android.

Can you please help me ?