So iOS 9 was announced at WWDC 2015 earlier today. The beta was released to developers today with the full release in the autumn.
So, I've installed the beta on my iPad Air 2. Here are some of the things I've noticed so far. Bear in mind I've only had it on the iPad for an hour or so. I'll update as I find more out:
A 6 digit passcode is asked for in addition to TouchID.
There is a search bar in Settings!! 👍
Newstand has been removed.
The new News app is missing at the moment.
Mutlitasking works well in landscape.
Spotlight is updated.
There is now a iCloud Drive app.
Will continue to update as I find more.