Listen to music while running.
Listen to podcasts while working around the house or on the way to work.
GPS to find places that I've never been.
Reading news and other useless crap while eating lunch or waiting in line for stuff.
Texting/IM'ing a few friends.
None of it is important, but it's all in one device, so it's less other crap to carry around.
Of all the above, the only one I feel any need for is Phone Calls.
Don't get me wrong, I'm not dismissing the right of everyone to make their own choices, just wondering how much of this 'need' for a smartphone (and need to constantly upgrade it) is actually just a case of people finding excuses to use something expensive, that they really don't need in their life, but have convinced themselves that they 'must have' it.