Besides mitigating against a potentially nasty Bluetooth bug, upgrading to iOS 9 today promises a whole host of benefits for iPhone and iPad users, including better battery life by way of a new low power mode, built-in mass transit direction for Apple Maps, and a split-screen mode that allows the iPad to run apps side by side.
But one of the most useful features might be one of the least flashy.
New for iOS 9 is the ability to return to the previously used app by simply tapping a small line of text in the top left corner of the screen. This means iOS users will no longer have to activate the task switcher by double tapping the Home button to return to the previously used app.
Yes, Apple's playing a bit of catch-up here since Android has had a software "back" button for some quite a while now, but that doesn't make the feature any less useful for iOS users.
For iOS 9, Apple has also lowered the amount of free space needed to upgrade: moving from iOS 7 to iOS 8 last year required 4.5GB of free space while only 1.3GB is needed this time around.
One final point worth noting is that watchOS 2, the next version of the software that powers the Apple Watch, will not be released today alongside iOS 9 because of a bug that was found at the last minute. Apple says the updated software will be released "shortly."
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