http://www.apple.com/iphone/design/

Creating an entitely new design meant inventing entirely new technology
When we envisioned the new iPhone, we landed on a remarkably thin and light design. But it’s nearly impossible to make a device so thin and so light without sacrificing features or performance.
We could have taken the easy way out and designed something more reasonable and less remarkable. But we didn’t. If the technology didn’t exist, we invented it. If a component wasn’t small enough, we re-imagined it. If convention was standing in the way, we left it behind. The result is 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. The intelligent, reversible Lightning connector is 80 percent smaller than the 30-pin connector. The 8MP iSight camera has even more features — like panorama and dynamic low-light mode — yet it’s 25 percent smaller. And the new A6 chip is up to 2x faster than the A5 chip but 22 percent smaller. Even with so much inside, iPhone 5 is 20 percent lighter and 18 percent thinner than iPhone 4S.

Making a thinner, lighter iPhone meant even the display had to be thinner. Apple engineers accomplished that by creating the first Retina display with integrated touch technology. Which means instead of a separate layer of touch electrodes between display pixels, the pixels do double duty — acting as touch-sensing electrodes while displaying the image at the same time. With one less layer between you and what you see on iPhone 5, you experience more clarity than ever before. All on a display that’s 30 percent thinner than before.

When we envisioned the new iPhone, we landed on a remarkably thin and light design. But it’s nearly impossible to make a device so thin and so light without sacrificing features or performance.
We could have taken the easy way out and designed something more reasonable and less remarkable. But we didn’t. If the technology didn’t exist, we invented it. If a component wasn’t small enough, we re-imagined it. If convention was standing in the way, we left it behind. The result is 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. The intelligent, reversible Lightning connector is 80 percent smaller than the 30-pin connector. The 8MP iSight camera has even more features — like panorama and dynamic low-light mode — yet it’s 25 percent smaller. And the new A6 chip is up to 2x faster than the A5 chip but 22 percent smaller. Even with so much inside, iPhone 5 is 20 percent lighter and 18 percent thinner than iPhone 4S.

Making a thinner, lighter iPhone meant even the display had to be thinner. Apple engineers accomplished that by creating the first Retina display with integrated touch technology. Which means instead of a separate layer of touch electrodes between display pixels, the pixels do double duty — acting as touch-sensing electrodes while displaying the image at the same time. With one less layer between you and what you see on iPhone 5, you experience more clarity than ever before. All on a display that’s 30 percent thinner than before.

When we envisioned the new iPhone, we landed on a remarkably thin and light design. But it’s nearly impossible to make a device so thin and so light without sacrificing features or performance.
We could have taken the easy way out and designed something more reasonable and less remarkable. But we didn’t. If the technology didn’t exist, we invented it. If a component wasn’t small enough, we re-imagined it. If convention was standing in the way, we left it behind. The result is 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. The intelligent, reversible Lightning connector is 80 percent smaller than the 30-pin connector. The 8MP iSight camera has even more features — like panorama and dynamic low-light mode — yet it’s 25 percent smaller. And the new A6 chip is up to 2x faster than the A5 chip but 22 percent smaller. Even with so much inside, iPhone 5 is 20 percent lighter and 18 percent thinner than iPhone 4S.

Making a thinner, lighter iPhone meant even the display had to be thinner. Apple engineers accomplished that by creating the first Retina display with integrated touch technology. Which means instead of a separate layer of touch electrodes between display pixels, the pixels do double duty — acting as touch-sensing electrodes while displaying the image at the same time. With one less layer between you and what you see on iPhone 5, you experience more clarity than ever before. All on a display that’s 30 percent thinner than before.