I limit my usage as much as I can, but am also in the group that as a minimum has to check my e-mail daily. When you do consultant work (like me), a new contract can slip through my hands while out on a cruise if I don't check in. Most of my jobs come via e-mail.
Now, I don't run around talking on my iPhone and constantly texting like some. However I do carry my phone as my camera and leave it in airplane mode.