iPhone 5: the thinnest, lightest, fastest iPhone ever. iPhone 5 is just 7.6 millimeters thin. To make that happen, Apple engineers had to think small, component by component. They created a nano-SIM card, which is 44 percent smaller than a micro-SIM. They also developed a unique cellular solution for iPhone 5. The conventional approach to building LTE into a world phone uses two chips - one for voice, one for data. On iPhone 5, both are on a single chip. Also this phone have the retina display.