QuoteOriginally posted by Supercracker:
 

QuoteOriginally posted by hvyhitter:
the phone uses towers and they may be few and far between and eat up battery life..........

Not necessarily true anymore. I can download all the maps (same ones as the Garmin) ahead of time and use it when there's no signal. Just like the Garmin.

I have an S4 and if I turn the app up to the highest battery usage settings (but phone in airplane mode) it eats about 10% of the battery every hour. Then I plug in my external battery (about the size of an Altoids tin) and get another 6-8 hours of time. [/b]

On float trip in AK last september we used an Iphone GPS system as soon as the supercubs dissapeared over the horizon.  Wanted to establish exactly where we were on the topo.  Took me less than five seconds to see that the lat and long from the phone app were completely bogus.  Took another minute to look around at the visible geo features and use a compass to precisely spot the sand bar we were on.

That sums up my confidence level in electronic nav.  Compass and topo for me!

However, my partner had a new camera that he had bought just before departure.  Sitting in camp reading the manual he found that the cam would record lat and long for a photo.  We checked the accuracy of the camera and it was dead on!