1. A system for generating an electronic manifest of underground facility locate marks, the system comprising: a GPS-enabled marking device to provide a set of GPS coordinates along a marking path of an underground facility marked by a locate technician using the marking device to perform a locate operation in a dig area; and a user device, comprising: a location identification unit to receive location tracking signals and determine a device geographic location of the user device based on the location tracking signals; a memory including a local image cache to store at least one aerial image of a geographic area including the dig area; an output device including a display; a communication interface to facilitate electronic communications, via a network, between the user device and at least one of a central server and an image server storing a library of aerial images, wherein at least some of the aerial images in the library include geocoding or other geographical identification metadata; and a processing unit to: control the communication interface to transmit, to the at least one of the central server and the image server, first information regarding the device geographic location of the user device as determined based on the location tracking signals received by the location identification unit of the user device, control the communication interface to receive, from the at least one of the central server and the image server, the at least one aerial image from the library of aerial images, wherein: the at least one aerial image is identified and retrieved from the at least one of the central server and the image server based on the first information regarding the device geographic location; the at least one aerial image includes the geocoding or other geographical metadata; and the at least one aerial image is stored in the local image cache, receive, from the GPS-enabled marking device, the set of GPS coordinates along the marking path of the underground facility marked by the locate technician, the set of GPS coordinates representing approximate locate mark geographic locations of the underground facility locate marks including at least one of a) paint, b) at least one flag, and c) at least one colored marker, placed on a surface above the underground facility by the locate technician using the GPS-enabled marking device to perform the locate operation in the dig area, control the display to represent, on the at least one aerial image, second information concerning the approximate locate mark geographic locations of the underground facility locate marks, based at least in part on the set of GPS coordinates received from the marking device and the geocoding or other geographical metadata included in the at least one aerial image, so as to provide the electronic manifest of the underground facility locate marks, and store, in the memory, the second information concerning the approximate locate mark geographic locations of the underground facility locate marks.