iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
Apple Granted Patent on Methods for Dimming Screens Based on Content Needs
The improved techniques reduce power consumption by lowering display intensity at appropriate times. In one embodiment, the display intensity can be controlled depending on the type of content being displayed. For example, when displaying certain types of content, the display intensity can be lowered from its otherwise high, constant intensity level. In another embodiment, the display intensity can be controlled depending on the characteristics of the content being displayed. For example, when displaying images that are light, the display intensity can be lowered from its otherwise high, constant intensity level. In still another embodiment, the display intensity can be controlled depending on the type and characteristics of content being displayed.Apple's battery-powered devices have long had the capability to automatically dim displays based on such criteria as power source (battery vs. wall power), ambient light levels and usage (dimming the display of a device that hasn't been used for a particular time interval). Dimming the screen based on content, such as when a particularly bright image is displayed, requires a more sophisticated approach, something that Apple has clearly been working on for some time.
Apple actually now uses a variation on this invention for its Passbook application in iOS 6 for the iPhone, automatically boosting the display's brightness to maximum when the app is launched in order to make it easier for scanners to read the 2D barcodes used on passes within the app.
The patent suggests that Apple's plans for content-sensitive automatic brightness adjustment could even extend as far as frame-by-frame or scene-by-scene adjustments when viewing videos, with users also being able to configure their own preferences for content-based brightness.