The most common screen resolution of modern high-end smartphones is Full HD (1920 x 1080 pixels), though there are also models with screen which has a resolution of QHD (2K or 2560 x 1440 pixels).
It is expected that by the end of 2014 will be presented displays for smart phones, the resolution of which will reach 3840 x 2160 pixels (Ultra HD). In production, they will be transferred at the end of this year or early next year, and hence the serial devices in the Ultra HD will be prescribed by the second half of 2015.
Six-inch panel with a resolution of 3840 x 2160 pixels will have 734 pixels density per inch pieces.