What is difference between Device Camera & Main Camera?
What is use of Device Camera Plane in Device Camera?
At the time of tracking which camera is used?
What is difference between Device Camera & Main Camera?
What is use of Device Camera Plane in Device Camera?
At the time of tracking which camera is used?
MainCamera
is a camera you have tagged as the "MainCamera" in the scene. As for the DeviceCamera, I have not seen this mentioned in Unity but I'd reckon it is the actual camera of your device.
In Metaio SDK plugin, the Device Camera refers to the physical camera on the device, while the Main Camera is the virtual camera that renders (or sees) the entire scene on the display. The Camera Plane is used to render the live stream from device camera.