According to Apple press release:

Apple® today announced iPhone® 5, the thinnest and lightest iPhone ever, completely redesigned to feature a stunning new 4-inch Retina™ display; an Apple-designed A6 chip for blazing fast performance; and ultrafast wireless technology—all while delivering even better battery life. iPhone 5 comes with iOS 6, the world’s most advanced mobile operating system with over 200 new features including: the all new Maps app with Apple-designed cartography and turn-by-turn navigation; Facebook integration; Passbook® organization; and even more Siri® features and languages.

Third generation of iPad brings many enhancements and innovations. New iPad has faster chip, better camera and great new display and much more. New Retina display brings four times more pixels than iPad 2 with razor-sharp text and richer text. The Retina display transforms the entire iPad experience. The Retina display on the new iPad features a 2048-by-1536 resolution, 44 percent greater colour saturation, and an astounding 3.1 million pixels — in the same 9.7-inch space. That’s four times the number of pixels in iPad 2 and a million more than an HDTV. Those pixels are so close together, that your eyes can’t discern individual ones at a normal viewing distance.