To use this app please check:
1) Your smartphone must have OTG USB support
2) Your USB camera should be UVC-compatile
3) Your OTG USB cable must be correct and reliable

USB camera must support UVC standard as well as your gadget must support OTG USB.
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Why the screen is black?
Let's say your gadget supports the OTG function and the USB camera is compatible with ANDROID. But the screen remains black.
Why? The reason may be in that you don't choice "Use by default for this USB device" in the dialog box.
This dialog box appears when you start the application with connected USB camera.
The appearance of this dialog box is guaranteed after the gadget is restarted.


Have you any questions?
http://endoscope.realvisor.net