I love my cellphone.
I've been without cell phones for long periods of time via deployments without issue. In Iraq I didn't have one until maybe the last 3 months, when someone gave me their old one. So I just sent texts to my buddy to let him know what movie to prep for movie night that night. Hah!
In Africa recently I didn't have one until half-way through when I went to Uganda. My mission commander had bought one, but offered it to me since I was more tech savvy. I ended up using it to text HFD all the time I even had to sneak out one evening to try to find an MTN (the minutes provider) booth still open to get more minutes. I probably wasted more money on minutes in Uganda than I care to calculate. And you know what? I HATED THAT PLAIN OLD PHONE!! It couldn't hold more than 80 texts! How am I suppose to flirt and re-visit cute texts like that!? I can't is the issue!
So! Smart phone for me, I love it, never looking back.
And GPS I <3 it. Although, I tend to read the map and directions before I set out on a course, so it's easier for me to get a hang of where it's trying to take me. GPS isn't perfect, so reading the map yourself ahead of time makes the whole thing work like magic.