Quote from InformationWeek Mobilty
The HTC J Butterfly is perhaps the Taiwanese company's most gorgeous smartphone yet. The new device, announced Wednesday, has a display that measures 5 inches across the diagonal and packs an eye-popping 1920 x 1080 pixels, making it a full HD display with 440 pixels per inch.
This puts the J on an entirely new playing field with respect to competing devices. Apple's iPhone 5, for example, has a 4-inch display with 1136 x 640 pixels. That equates to 326 pixels per inch. Apple calls this high-density screen a Retina Display, which it uses for its marketing materials. There's no doubt the Retina Displays look great. But the J beats it. By a lot.
The J also beats Samsung's Galaxy Note II by a wide margin. The Note II's 5.5-inch display has 1280 x 720 pixels, giving it a pixel density of just 267 pixels per inch.