I have played with this a little bit on Truman. I can find GPS coordinates on my home computer but on the iPhone app they are not listed that I can find. The app does have a GPS function, but uses triangulation from cell towers. You will find that there is a delay as the phone location is locked in. This is a bit of a problem when moving. You also have some difficulty reading the small screen in the sun if you use bifocals. It works but it takes some effort. My next step is to wright down some coordinates at home and learn how to use that function on my hbird 587.
God bless Charlie Brewer and Bobby Garland.