iOS 9.3 contains a new Night Shift mode, which basically Sherlock’s f.lux, along with new Touch ID security options for the Notes app, improved CarPlay functionality, an upcoming Multi User mode for schools, and much, much more.
Put it this way, this update is so big that Apple has devoted an entire web page for previewing many of the new features. That’s something that it usually only does for major version number releases, but the content contained in iOS 9.3 apparently warranted the fanfare.
Night Shift
Night Shift is a brand new feature that is very much like f.lux. In fact, when the folks at f.lux made it possible to install their app on iOS 9 thanks to Xcode’s new sideloading capabilities. The project was shut down not long after. Now it’s clear as to why.
CarPlay
iOS 9.3 adds new features to CarPlay like enhanced Apple Music support. Now you can view the New and For You sections in Apple music to find curated music based on your tastes. A new Nearby feature in maps makes it easier to find points of interest like gas, parking, coffee, etc., in a single tap.