Straight talk, which uses both Verizon and AT&T towers works in most areas (data 3G/LTE+), and I've not walked into an area where I haven't had cell service (call/text). I've explored most of the parks hiking trails.
Depends on your provider. It can get spotty.
I have AT&T and it's spotty, but people w/ Verizon seemed to have a little better service. Hope this helps.
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