According to an article in the Korea Herald, LG will introduce a smartphone with a 5-inch screen boasting a full 1080 HD display. This means that the vertical measure of the display will be 1080 pixels deep, which is equivalent to large-screen HDTV sets. To scrunch all those pixels into such a tiny screen a pixel density of 440 ppi is required, which is technically higher than even high-quality art books. This will mean very crisp text – albeit still on a backlit screen, if that matters to you.
As a comparison, the iPhone 4S offers a 3.5-inch 960 x 640 display and a pixel density of 326 ppi.