Oh is that only with 6s plus? I got the 6s
Yes, and possibly the 6 Plus as well. Only the "Plus" sized iPhones have rotation of the home screen. Also they have rotation of some other apps like settings and the App Store, as well as dual-pane UI features like on iPad. For example, on iPad, messages has the list of conversations on the left and the conversation's contents to the right. The 6 Plus and 6S Plus have this as well in landscape. The 6 and 6S only show the conversation in landscape, no list to the left. Same goes for settings
I'm still running 9.0 and it works fine plan on keeping it that way at least until 10 arrives but won't jump right into 10 will wait several months after.
I've learned that if your device is running smoothly and great battery then there is no need to rush into these updates especially if your device came with 9.0
You only have till September to update to the newest version of iOS 9, which is MUCH MUCH MUCH MUCH smoother and FAR more stable and quick. If you're on iOS 9, it is strongly advised to update to any 9.x.x release. for example if you're on iOS 8, any 8.x.x update is pretty safe and highly recommended to upgrade to. However if you're on 9.x, it would be good practice to be wary about upgrading to a 10.x.x release. Particularly 10.0.x.
So yeah, going up a major version, like iOS 9 to iOS 10, or iOS 7 to iOS 8 would be more risky and good to be wary about. More minor releases like a .1, .2, .3 etc
of the same version is actually very good to upgrade to because they're meant to fix things and make your device smoother and faster. And the iOS 9.1, especially iOS 9.2, and 9.3 updates have done just that. My iPhone 6 and particularly my iPad mini 2 were HORRIBLE, *very* choppy and slowww with iOS 9.0.x and 9.1. It wasn't until iOS 9.2 that things were "okay" but still not great. Tolerable at least. I didn't want to sell my devices anymore. Then with iOS 9.3? They run like a total dream... Really good. And you get Night Shift, which is awesome. It makes your screen have more of an amber tone at night which is much easier on the eyes when using your phone in the dark for example. I really like it.
I *highly*, *HIGHLY*, recommend that you update to 9.3.3. It made my devices so much better to use.
If you want to jailbreak though, don't upgrade. iOS 9.0.x can currently be jailbroken, but iOS 9.2+ cannot be. still no word on when a jailbreak will come out for these newer releases of iOS 9, and it's been months.
So yeah. If you jailbreak, jailbreak while you can. If you don't jailbreak though, for the love of god, update the hell out of your device to 9.3.3. You won't regret it. My devices perform COMPLETELY differently under 9.3.x as opposed to 9.0. It was like buying all new devices, after moving up to 9.3. Be wary when iOS 10 drops though.