I would say, think about what you want to use your cell phone for. Are you going to use it to have for just in cases of emergency? Will it be replacing your land line? Will you use it for business purposes as well as personal use? Does your budget allow for a plan that includes unlimited everything that can cost you well over $100 a month for just one phone or are you limited?
Depending on your answer to these, there are pre-paid plans that will get you a phone to keep you connected for just in case of emergencies and there are plans that are unlimited everything.
Definitely shop around to the various cell phone providers to see which gives you the best bang for your buck.
Also, if you're gonna go with a smartphone, go with Android. Android based phones keep you connected to everything. Google has great ways to keeping all you use connected as one, from gmail, to Google drive, to your Google calendar, to Google+ and more. But then again, I am a tadbit biased and love Google for everything.