Apple comes to controversial iOS 9 Wi-Fi Assist's defense
In a nutshell, Wi-Fi Assist is designed to save your connection from crapping out when you're in a weak Wi-Fi zone by switching you over to cellular wireless. And the feature is on by default.
The problem there, if Wi-Fi Assist's tolerance for Wi-Fi shakiness is low, is that you could chow down a lot of your data plan, which of course would be worrisome and possibly expensive if you don't have unlimited data from your carrier. We reported earlier this month about how at least one university IT department and at least one carrier was warning users about the feature (See "Apple Wi-Fi Assist: Threat, Menace or Neither").
REVIEW: iOS 9 delivers polish and stability
While a bit of Apple reaction to all this could be found in its support forums, it wasn't until this week that the company really issued any public support or clarification around Wi-Fi Assist as it does here on the Apple support page.
On the page, titled "About Wi-Fi Assist," Apple explains that "With Wi-Fi Assist, you can stay connected to the Internet even if you have a poor Wi-Fi connection."
Apple says the feature works with most apps (though only lists Apple ones, like Music and Mail). Apple does say that you'll see the cellular data icon in your device's status bar if Wi-Fi Assist has kicked in, and assures customers that "you might use more cellular data. For most users, this should only be a small percentage higher than previous usage."