That thing was Haptic Touch, Apple's 3D Touch replacement on the iPhone XR. Instead of pressing on the display, as 3D Touch devices require, Haptic Touch is triggered through a long press on the screen.
At that time, Haptic Touch was only available in the iOS Control Center, on the lock screen shortcuts, and the keyboard to use as a trackpad when editing text.
Pressing on a link, peeking at a conversation in Messages, or, most notably, peeking at a notification in Notification Center wasn't possible. Being able to quickly view and triage alerts on the lock screen was something I sorely missed when using the iPhone XR.
Then, last week, Apple released iOS 12.1.1, and included in the change log was "Notification preview using haptic touch on iPhone XR." That's in addition to fixing that super annoying FaceTime feature that moved the camera swap button starting in iOS 12.
After installing the update on my review unit, I let a few notifications pile up and then, with a long press, was able to view the notification and its appropriate actions on the lock screen without having to swipe left on the alert and select view.
The haptic feedback felt when triggering the feature is just like that on the iPhone XS Max, if not a touch more pronounced. There's a tap when the XR recognizes a long press as the message appears to pop out of the notification list. Then, there's another haptic tap when you lift your finger. Overall, it's incredibly well done.
With Apple continuing to make small, but impactful changes to the iPhone XR's software, combined with stellar battery life and an impressive camera, the iPhone XR continues to be the most appealing phone Apple announced this year.
Apple switched up release strategies a bit in 2018 with the two high end $1,000+ models released initially, followed by one priced $250 to $350 less. The iPhone XR arrives in six color options and honestly it may be the best option for the masses.
Since Apple didn't give you a manual listing the gesture changes you have to get used to when you switch to the iPhone XS, iPhone XS Max, or iPhone XR, use these cheat sheets to familiarise yourself with what you need to know.