Hi Mike Phillips,
Greetings from Syncfusion.
We have checked your requirement and would like to inform you that, we can achieve this by using the OnSizeAllocated framework method. In this method, we can find the device orientation based on the Height and Width of the layout. So, we can load the Circular/Linear gauge from it and the required values of the Gauge are bound from the ViewModel.
We have prepared the sample for the same. Please get it from the below link.
Please find the below user guide documentation link for more information about circular and linear gauges
Please let us know if you have need any further assistance.
Regards,
Eswaran.