Japanese electronics giant Sharp has announced production of 5.5" displays with 4K (3840 x 2160) resolution. They'll hit the market next year. The display will have a pixel density of 806 PPI. It's not known yet which smartphone makers will build devices with these screens. The displays cost significantly more than a more typical 1080p or 1440p display, so they'll probably only make it into high-end phones. On the other hand, this will help to drive down prices for lower-resolution displays, so it could indirectly benefit everybody.

http://hardware.slashdot.org/story/1...tphone-display