Most common use is hiking, for which I want a more readable display than my iPhone and freedom from battery worries. But all of this too:
establishing an accurate position of something
multi-day cycle ride navigation along a pre-established route
recording the route of a car trip (not necessarily navigating it)
boating
hopefully in the future: flying an ultralight plane.
I am familiar with the use of the eTrex 20 (this search is prompted b