If you’re an iOS Public Beta tester, Apple has just released iOS 9.3 public beta 1. On your device, just go to Settings > General > Software Update to acquire the update over-the-air.
The release comes days after iOS 9.3 beta was released for developers, which includes new features such as Night Shift mode (aka f.lux) and more.
Apple also released OS X 10.11.4 for public beta testers as well. Not part of the public beta program yet? You can sign up for it here.