Oh my goodness I just wanna schmak you. JK

The point of these things is to have the connectivity and many features of a laptop without having to lug around a laptop. And some people don't feel like paying for a 3G agreement.
If you don't understand what it's for, that's ok too. I don't understand what dressing like a woman is for but plenty of men find it practical for their lifestyle. Some people find video games pointless, but others would strongly disagree. If you don't like it, then I strongly suggest you don't buy it or else you're in for certain disappointment.
Or else, you could be in for a pleasant surprise. At first I thought Twitter was an impractical chore. But now I'm quite addicted.