For an iPhone user, features like fast charging, an always-on/ambient display, front-facing stereo speakers, or being waterproof might be "new" features that would be fitting answers to the question, but are common on various Android devices. For Android users, the idea of a "new" feature gets difficult because there are so many options out there and all of those options and more can be found in one device or another. A foldable smartphones would fit the bill, but the best estimates say we're still at least a year away from that.
The one feature we've heard rumored that doesn't exist on either platform would be wireless charging from a distance, and that could well be made available this year. And, it's possible that the features Cook is talking about are software-based, not hardware, so that could include massive updates to voice control or adding more augmented reality features.
So, what's a new feature that is realistic to come in a new device this year that would fit your definition of something you wouldn't be able to live without once you have it?
Sound off in the comments!