This post is a bit late, but if you have not updated your iPhone to iOS 9.3.1 yet, it’s safe to do so. And if you have 9.3 but have not updated to 9.3.1, do so because 9.3 had a few annoying bugs.
This article tells you about the new stuff. Not much very exciting, but I do like the new Night Shift option. As you may, or may not know, most electronic screens emit a lot of blue light — and that is the light that stimulates your brain and keeps you awake at night.
If you have trouble going to sleep, the obvious solution is to turn off electronics a few hours ahead of time. If that does not work for you, then Night Shift is a big help. Night Shift, at a predetermined time, reduces the blue in your display. This results in giving everything a slightly orange hue. The Night Shift options can be found in Settings under Display & Brightness. You can set the times for when it is active and adjust the “Warmth” of the display. Warmer means less blue and more orange.
I have come to really like Night Shift. I like the softer cast at night and if I choose to look at my phone when I wake up at 3 AM, the orange cast of the screen is very gentle.
Finally, as always, it is important to keep your computer’s OS up to date. OS X 10.11.4 was recently released for all Macs and Microsoft is continuously releasing updates.