Developers got their hands on iOS 9.3 a couple days ago, and now public beta participants can do the same. The update (build 13E5181f) includes several new features such as Night Shift, and multi-user support for iPads in schools.
iOS 9.3 made the jump to public beta
Night Shift mode changes the color cast of your iPhone, iPad, or iPod touch screen to have a warmer and more reddish look at night to help users avoid sleep issues. The update also includes the ability to passcode lock individual Notes entries, and view Apple Watch activity in the Health app.
CarPlay gets improved support in iOS 9.3, and the ability to assign multiple users to a single iPads in classrooms should please schools that can't afford to buy a tablet for every student.
Apple typically doesn't add in major new features to its operating systems outside of its annual big upgrades, so that makes iOS 9.3 something of an anomaly. The company has historically shown off features for the next upgrade at its annual Worldwide Developer Conference in the spring, and presumably will do just that again this year.
Assuming Apple is planning on on rolling out even more big features in iOS 10—or as TMO dubbed it on our Daily Observations podcast, iOS Voldemort—there will likely be some over the top announcements at WWDC.
Participating in Apple's public beta program is easy, and it's free. You can sign up at the Apple beta participant website, but don't install the software on devices you need for mission critical activities because you may have to deal with bugs and crashes. After all, the software is still in a beta testing phase.