Jim,
One thought: I can change my portable vehicle Garmin GPS to different formats for coordinates. Also my hand held Garmin GPS can do the same. I believe that you can also change the coordinate format on Google Maps and Google Earth.
The problem I would have with phone apps is that when I'm out on claims I am usually out of cell range, which won't let me use Google Maps. I am not on unlimited data anyway, so I limit non-Wifi data even when I have cell coverage.
Wayne