I'm off up north soon and preparing to leave my main phone and ipad at home. At my dad's house, I can't make a phone call indoors let alone receive email. And it's the same at my second favourite pub up there, want a taxi and you have to walk to the bottom of the car park (and this is the Pennines so it's raining) to get a signal.
However, every cloud has a silver lining and so when I leave work saying "Sorry but I'm not contactable" and they say "Ok we'll only call you if it's urgent" I get to say "No really. I'm not contactable."