DeviceStatus.DeviceFirmwareVersion Property
July 26, 2012
Returns the firmware version running on the device.
Assembly: Microsoft.Phone (in Microsoft.Phone.dll)
This property does not return the OS version, which can be retrieved using System.Environment. We recommend that the value be a string that can be parsed as a System.Version structure and that it be incremented in a logical manner as newer hardware is released, but this is not required. This value may be empty.
For more information about the DeviceStatus API, see Device Status for Windows Phone.