I am considering buying this adapter
https://www.amazon.com/dp/B01GGKYXVE/ which will let me connect any normal external PC USB device (not ones designed specifically for smartphones) to a smartphone with a USB-C port. My intent is to use my generic UVC (USB-video-class) USB webcam on my smartphone (does not require dedicated drivers, and on my Windows PC it works as soon as plugged in), but I don't know how Android handles webcams. I know it normally detects the two that are hardwired into the phone (the front and rear facing cameras). And most camera apps have a way of switching between these 2 cameras. However, what happens if a 3rd camera is present, such as one connected via the USB port? Does the camera automatically override one of the two built-in ones, so that when switching between the cameras in an app, one of the two cameras is now your USB webcam (and thus ignores one of the two internal ones)? Or does it add a 3rd camera to the device, such that you can cycle through all 3 cameras in the app when you tap the button to switch cameras? Or does it just not work at all, never recognizing the external camera?
If anybody has ever tried this (using a USB-C or micro-USB adapter to connect a generic webcam to their Android phone), please let me know how well that worked. I don't want to waste my money on this adapter if an Android phone will not recognize a webcam when it's plugged in.