USB Camera is a tool that lets you connect a webcam to your smartphone or tablet and use it as an alternative to the device's own camera. Although it's true that the interface could be more intuitive and the quality and resolution offered by the connected camera could be better, USB Camera is a free option worth considering for anyone who wants to replace the camera on their smartphone or tablet for whatever reason.
In order to use USB Camera correctly, you'll need an Android device, a webcam that can be connected via USB, and an adapter compatible with the port of your smartphone or tablet. Once everything is connected, you can start configuring aspects of the transmission, although you must bear in mind that the quality offered will never exceed 640p, regardless of the resolution at which your camera is capable of broadcasting.
USB Camera is compatible with any app that needs a camera to work properly, such as Skype, Whatsapp, the device's own camera app, and more.