Iphone 4.

While everyone else was busy trying to keep up with iPhone, we were busy creating amazing new features that make iPhone more powerful, easier to use, and more indispensable than ever. The result is iPhone 4. The biggest thing to happen to iPhone since iPhone.
 

FaceTime

People have been dreaming about video calling for decades. iPhone 4 makes it a reality. With just a tap, you can wave hello to your kids, share a smile from across the globe, or watch your best friend laugh at your stories — iPhone 4 to iPhone 4 over Wi-Fi. And it works right out of the box. No other phone makes staying in touch this much fun.

Retina Display

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.