From MacRumors.com…
There are quite a few major changes in iOS 9, like split-screen multitasking for the iPad, improvements to search and Siri, under-the-hood performance boosts, and revamped apps, but there are also dozens if not hundreds of lesser-known tweaks and refinements that make the iOS 9 experience better than ever before. Weve had a lot of hands-on time with iOS 9, so weve rounded up a list of the best hidden features in new operating system. These are great little changes youre going to want to know about, so make sure to check out the video and the list below.
The one I’m probably most excited about…
Go Back to App – When you tap on a Notification or a link in Safari or another app and it opens a new app, you can go back to the previous app using a handy new “Go Back” button. The “Go Back” button will stick around for about a minute before disappearing, so you can switch quickly between apps if you just want to glance at something real quick.