iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
Claimed 4.7-Inch iPhone 6 Rear Shell Shown in Video With iPhone 6 Mockups, iPhone 5s
In line with previous rumors, the shell is significantly thinner than the iPhone 5s and has all of the anticipated cutouts for the iPhone 6, including a mute switch and elongated volume buttons similar to those on the current iPod touch. The shell also houses a cutout for a SIM card tray and possibly the power button, which may be moved from to the top edge to the side to make it more accessible when using the larger phone single-handed.
Apple may unveil both the 5.5-inch and the 4.7-inch version of the iPhone 6 simultaneously, with September 19 as a possible launch date. Based on Apple's past releases, a media event to introduce the new hardware would come roughly a week and a half prior to that date. Both models are said to include a faster A8 processor and new camera options that may see the 4.7-inch version ship with an advanced lens and the 5.5-inch version exclusively use optical image stabilization to improve photo quality.