This was confirmed in a tweet by developer Bryan Irace where he filed a Radar about the feature being missing in iOS 11. He later got a response from an Apple engineer who confirmed that the feature was not missing by accident, but rather it was removed intentionally, although the exact reason behind the removal is unclear.
Apple engineering has confirmed that 3D Touch multitasking was intentionally removed in iOS 11. I am livid. pic.twitter.com/kiCcLq9XMB
— Bryan Irace (@irace) June 30, 2017
If you’re learning about this feature for the first time, basically what iPhones with 3D Touch can do is press deeply on the left edge of their iPhone’s display to launch the app switcher, and from there they can drag their finger across to switch between apps seamlessly. This is versus the alternative/existing method where you would have to double press on the home button to bring up the app switcher.
Like we said we’re not sure why the feature is removed, and some have speculated that maybe it has to do with the iPhone 8’s rumored bezel-less display, although we don’t see why both features couldn’t exist side-by-side, but either way if you’ve been extremely reliant on it, we guess it’s time to start getting used to the alternative.