iOS 9 on the iPad Air 2
iOS 9 is now available to download as a public beta. Should you decide to explore it (my recommendation: do this only on a non-primary device that you've backed up), Apple's latest OS has a number of iPad-optimizing features we've awaited for years.
Split View
For iPad Air 2 owners only, you can run two apps side by side at last. There are already tablets that can do this (Samsung, Microsoft, etc.), but it's nice to see it on the iPad.
Split View
Apps snap in place in two set configurations; you can adjust the size of each by sliding.
Slide Over
A related cousin to Split View, but it runs on other iPads, too. You can swipe an app from the side and have it pop up to quickly write a message or check an email, then pop back to what you were doing.
Slide Over
Slide Over works a bit like a side-loading dock.
Onscreen trackpad
Behold, the onscreen keyboard now doubles as a trackpad! Hold down two fingers, and suddenly you can slide the cursor around and easily select text without reaching up to tap.
Picture-in-picture video
Another iPad Air 2-only feature, this lets you pop a video out of its app and float while you're working on another app somewhere else. Samsung's recent Note tablets have this feature, too.
Picture-in-picture video
A tiny movie, floating in the middle of my home screen.
News
Apple also has a new News app. It's a news reader, much like other news-consolidating apps like Flipboard. Right now, it's hard to tell what it brings to the table.
Other iOS 9 features, too
There are lots of other iOS 9 features of note, including improved Siri, better promised battery life, and a more Evernote-like Notes app. Read all about them here.