Currently, the nearest point operation does not support three-dimensional analysis. We in our mobile application deal with a lot of three-dimensional data and often use the nearest coordinate method of the GeometryEngine. Since obtaining the altitude of the nearest point from an input geometry is critical to us, we resort to a lot of hacks to obtain the z-value of the resultant co-ordinate after using the nearest coordinate/vertex method. It would be great if such methods of the GeometryEngine supported the three-dimensional analysis of the input data.