iPhone 4 has two cameras: One on the front, which focuses on you. And one on the back, which focuses on everything else. FaceTime lets you switch back and forth between them at any time during a video call. All you have to do is tap a button.The Retina display on iPhone 4 is the sharpest, most vibrant, highest-resolution phone screen ever, with four times the pixel count of previous iPhone models. In fact, the pixel density is so high that the human eye is unable to distinguish individual pixels. Which makes text amazingly crisp and images stunningly sharp.iPhone 4 introduces a whole new way of multitasking. Now you can run your favorite third-party apps — and switch between them instantly — without slowing down the performance of the foreground app or draining the battery unnecessarily.1 This smarter approach to multitasking is available only on iPhone.Shoot your own movies in high definition. Capture impressive video even in low-light settings, thanks to the advanced backside illumination sensor and built-in LED light. Then edit and create your own mini-masterpiece right on iPhone 4 using the new iMovie app — with Apple-designed themes, titles, and transitions.Take beautiful, detailed photos with the new 5-megapixel camera with built-in LED flash. The advanced backside illumination sensor captures great pictures even in low light. And the new front-facing camera makes it easy to take self-portraits.