int count = (UICamera.GetInputTouchCount == null) ? Input.touchCount : UICamera.GetInputTouchCount();
for (int i = 0; i < count; ++i)
{
var touch = (UICamera.GetInputTouch == null) ? Input.GetTouch(i) : UICamera.GetInputTouch(i); // <-- actual Unity touch
// do whatever you want with it
var nguiTouch = UICamera.GetTouch(touch.fingerId); // <-- this gives you the corresponding NGUI touch
}