I use the iphone
(with navionics) as my primary navigation instrument. My boat
has a gps/chartplotter but i havne't gotten around to figuring out how to operate it yet and the iphone
is handy because it's in the cockpit
with me, i can see exactly where i am and i can make course adjustments on the fly using the touchscreen. I will use the chartplotter
for long travels though.
ps:- So vote 1, vote iphone.