Samsung Galaxy S4 recommended! Its large screen size helps you surf the net or play games much better. If you like reading ebooks, the best choice I think. You can load PDF formats directly. Many benefits you will be able to discover by yourself.
If u want the easy to learn features, iTunes, apps and syncing your data between devices then IPhone4s is your best choice. Or u could buy a Samsung Galaxy that has out of this world features/graphics and non-breakable phone, so be it