You may have an office GIS standard that has already been adopted. So certain data formats and Coordinate Systems may have been adopted for transferring map data. The challenge is in finding a field unit that is compatible with your desktop GIS application. There are difficulties using GPS with most desktop GIS applications. Most applications are large and expensive.
Substantial training is required.
They have additional features to layout, format, analyze, view, theme, and print finished maps. These features are not useful in the field, they slow down the user and take up disk space and processor power. Desktop GIS applications also redraw the display more slowly. Therefore, in addition to increased software cost, they require more expensive hardware, and additional training. What we want is a small field package that runs on low cost hardware including the palmtops, handhelds, sub-notebooks, notebooks, and small laptops.