The iPhone, from the very first day it was released to the market, has been known for its user-friendly navigation and design. What makes it easy to use? Well, to begin with, there's only one button, the latest series have no buttons at all. Furthermore, the touch and feel of the phone is delicate and light making it less of a hassle to carry around. The basic structure of the phone has not changed much since it was first launched in the year 2008.