I actually can't think of anything that I need that my smartphone doesn't give me at this point in time.
Look and feel, camera, e-mail, messaging, social media, apps available and general ease of use with good battery time are just about perfect for me with my chosen device.
Too much is a determent as far as I see.
I think name brand device manufacturers are having difficulty figuring out what the best balance is.
These days it's getting very hard to charge big money for phones that really don't elevate the technology by much.
I can think of a few things phone's could do that people would appreciate:
*Not have ads
*Not have in-app purchases
*Interface with the human being in a more human-centric manner. rather than tapping on glass
*type in a less annoying way
*have longer than a days battery life
*have a display that you don't have to hold 1 foot from your face and peer at, to see clearly
*be a size and shape that is comfortable and ideal for using as a phone
*be able to be used like a piece of paper,
*Be able to anticipate your needs and act proactively
As far as need goes, people don't "need" smartphones.
They only came to feel like it was a need when they were in commonplace useage. In that sense, nothing "new" would be needed, and would become universally needed, the moment it was universally used, whether that was a jack in the back of your brain, a chip in your hand, or whatever else.
Before smartphones people used features phones and they lacked nothing. Before feature phones they used basic mobile phones, and they lacked nothing. Before mobile phones, they used landlines and pagers, and they lacked nothing. Somewhere back in history, is a half naked dude roaming the African plains, and he lacked nothing. These are essentially conveniences that we pay for with our extremely long work weeks, that make us slowly more dependent, and less resilient, until we end up like the fat people with screens glued to their face in wall-e.