iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
Schiller on iPhone Unlocks and Incompatibility
Schiller clarifies that this is not an intentional move to disable unlocked iPhones:
''This has nothing to do with proactively disabling a phone that is unlocked or hacked,'' Phil Schiller, Apple's senior vice president of worldwide product marketing, said in an interview. ''It's unfortunate that some of these programs have caused damage to the iPhone software, but Apple cannot be responsible for ... those consequences.''
To clarify, this appears to affect iPhones that have been specifically SIM Unlocked to use other carrier SIM cards besides AT&T. iPhones otherwise "hacked" to install 3rd party applications are unlikely to be affected in the same manner.
There has already been one tutorial on how to relock your iPhone. We'll be posting coverage of apps, tools, tutorials at our iPhone blog.