I think it has to do with personal preference. Imagine doing the things you mentioned on your phone, but a bigger screen. That's basically what a tablet is. I prefer my laptop, with a mouse and real keyboard. I have a friend who does everything on her phone. I could never do that! I do have a small tablet (not an iPad) but only use it for games, which I do like it for.
Are you a Mac/iPhone owner? Is that why you are considering an iPad? If not, there are several Android tablets. I use a Mac laptop, Windows laptop in the household, and Android phone and tablet. But not everyone is tri-lingual :)
All these electronics travel with us!