Apple has released the fourth public beta version of iOS 9.3. Members of the Apple Beta Software Program can grab the update as an over-the-air download through Settings > General > Software Update on a registered iPhone or iPad.
Apple seeded the fourth developer beta of iOS 9.3 earlier this week. iOS 9.3 is expected to bring a number of new features and improvements to iOS, including a new Night Shift mode for better nighttime use, along with changes to Notes, News, and CarPlay. The update will also bring along a number of changes for the iPad in education.