There are times when you might get the System.MissingMethodException ‘Xamarin.Forms.Device.get_RuntimePlatform’ when working with the Xamarin.Forms application and using the method Device.RuntimePlatform to identify the device platform.
Device.RuntimePlatform is the preferred way to find the platform that the application is running on from Xamarin.Forms 2.3.4. You need to ensure that both the PCL and the Android project has the latest Xamarin.Forms installed within the project. You can update it from the NuGet Package Manager.
