You would use lantitude and longitude to help navigate if you ever lost a GPS or when marking things on a map. It can also be useful while sailing.
Both use it. Aviation uses it when they are up in the air and cannot see the ground below them. The air control tells them cordinaites they should fly to. Where-as, transportation also uses it when they need to find a specific thing, like trains finding a station.
GPS works through satiliete signals in space reflecting points on earth into your devices.
They are rather accurate depending on wether your device is working and if the satiliete is working. A form of GPS (Kind of) is sports. They use the same system to broad cast live.
