I'm not sure what you mean by recent, but I think the most interesting concept in UI/UX that I can think of off the top of my head is the OS-level back-button o

I'm not sure what you mean by recent, but I think the most interesting concept in UI/UX that I can think of off the top of my head is the OS-level back-button on Android. I love Apple laptops, but the OS-level back-button on Android is at least 1/4 of the reason I prefer Android to iOS. It's just such a specific and weird feature that I never would have had the audacity to think "hey, every single application will benefit from this being a constant fixture in the operating system." I know that applications can add a back button when they feel it's necessary, and I know you can swipe to go back in iOS in various applications, but it's just not the same.