how big is the screen on the iphone 6s
iPhone 6 display is 4.7 inches in size.
IPhone 6
The most significant changes to the iPhone 6 and iPhone 6 Plus are its displays; both branded as "Retina HD Display" and "ion-strengthened", the iPhone 6 display is 4.7 inches in size with a resolution of 1334x750 (326 ppi, minus one row of pixels), while the iPhone 6 Plus includes a 5.5-inch 1920x1080 (1080p) display (401 PPI). The displays use a multiple-domain LCD panel, dubbed "dual-domain pixels"; the RGB pixels themselves are skewed in a pattern, so that every pixel is seen from a different angle. This technique helps improve the viewing angles of the display.

To accommodate the larger physical size of the iPhone 6 and iPhone 6 Plus, the power button was moved to the side of the phone instead of the top to improve its accessibility.
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IPhone 6 [SEP] Displays
The most significant changes to the iPhone 6 and iPhone 6 Plus are its displays; both branded as "Retina HD Display" and "ion-strengthened", the iPhone 6 display is 4.7 inches in size with a resolution of 1334x750 (326 ppi, minus one row of pixels), while the iPhone 6 Plus includes a 5.5-inch 1920x1080 (1080p) display (401 PPI). The displays use a multiple-domain LCD panel, dubbed "dual-domain pixels"; the RGB pixels themselves are skewed in a pattern, so that every pixel is seen from a different angle. This technique helps improve the viewing angles of the display. To accommodate the larger physical size of the iPhone 6 and iPhone 6 Plus, the power button was moved to the side of the phone instead of the top to improve its accessibility.