All Snapdragon 800-based phones, and there are quite a few of them, and there will be more in the coming months (and of course later even more chips doing the same). Right now it's the one you said, LG G2, Sony Xperia Z1, Samsung Galaxy Note 3, and soon the Nexus 5.

Now I'm not 100 percent sure if every single one of them has that as a user-centric feature (maybe they didn't enable it), but the chip supports 4k video recording.