Why ARCore doesn't support Nexus 9?

I need help about Google ARCore. Actually Unity app working in Nexus 9 but Google ARCore Android app doesn't support it. Also I know about supported devices.

But I want to know about what's the difference between Android ARCore & Unity ARCore? Why Unity AR app is working in this device but Google ARCore is not supported its own native SDK?

Solution

ARCore is the plugin developed and maintained by Google. There are ARCore SDK, ARCore NDK, ARCore iOS, ARCore Unity (where you can develop apps for iOS and Android simultaneously), ARCore Unreal. Unity also supports Vuforia SDK that has its own engine as well (developed by PTC) and/or can compile apps from Unity's ARCore and ARKit libraries. It depends.

In Unity, ARCore is directly integrated into the engine – you know there’s a little checkbox for it in the XR settings – and it’s compatible with Unity versions 2017.1 or later.

But.

Unity has its own AR engine. It allows Unity to compile apps that can be run on even officially unsupported devices. That sounds strange. But for Google there are obvious reasons for unsupporting Nexus 9 officially:

Nexus 9 may have no real Gyroscope sensor (it may have virtual Gyro)
Nexus 9 will be in the list of supported devices a little bit later (although it's unlikely, because it released in 2014)
possibly Nexus 9 has hardware issues
it does not meet the minimum software requirements for ARCore
there are Google's business preferences (HTC and Google are competitors, aren't they?)
etc, etc, etc.

Hope this helps.