Your comments are correct for phones that relay on cell tower for location determination.
The Andriod phones have a true gps receiver, so the lack of cell tower coverage doesn't limit their useability for nav purposes (or for mountain hiking...). I understand the new, maybe more recent iPhones also now have a true gps. Although I have milspec Casio clamshell which has been an excellent phone - waterproof - after a buddy tracked the progress of last Sunday's thunderstorms to a T with his iPhone weather radar app, I feel that functionality is a must have...especially if you are sailing a smaller boat.
I need to figure out whether an Android is good enough, or even better...
That's interesting. So the cell phone has a completely separate satellite GPS receiver/antenna too, distinct from the cell antenna/receiver?
See, now you know why everyone calls me a luddite.
But I'm still trying to figure out what that would do for me.
We have a cartographic gps on the boat. It's waterproof and floats, and has a massive database of charts, maps, and other almanac-type information. It works anywhere in the world.
Frankly, our GPs unit has far more capability and functionality than we need. And it cost quite a bit less than an i-phone, and requires no monthly subscription. Any time I've looked at i-phone service/data fees, there's no way I could justify it.
Again, luddite talking, so FWIW....