If there was an alternative to GPS that provided higher resolution tracking, what applications would there be for it in GIS?
Note that this means higher resolution, but not necessarily higher accuracy. For instance, the absolute position (lat/long) would not be more accurate than GPS, but the relative movement during tracking could be within a few inches. This means you could get a very detailed track recording of a device's movement, allowing you to see small changes in position or elevation. If you were to carry this device while hiking a trail, you could see elevation changes with 1-5 inch resolution. I imagine this might be useful for GIS, but I am not familiar with the market.