Yes, I know that some smartphones shoot decent 4k. I snuck a little 4k in from my Galaxy Note 4 on my last project. This is different though. We're talking high quality 4k with decent sized sensor and a large aperture lens from a pocket sized camera. You could stick footage from this on a major motion picture and it would look great.
http://www.cnet.com/uk/news/sony-introduces-rx10-ii-rx100-iv-and-7r-ii-cameras-bring-pro-level-features-performance-to-compacts/
http://www.cnet.com/uk/news/sony-introduces-rx10-ii-rx100-iv-and-7r-ii-cameras-bring-pro-level-features-performance-to-compacts/