It depends. There are many significant differences between the 4K cameras found in mobile devices and those found in 4K camcorders, but they all boil down to the quality of the video they produce. A 4K video from a camcorder will be of much higher quality due to how 4K camcorders handle adverse lighting conditions, motion, and audio. A 4K video from a phone will be very clear – it can often produce videos that look good when played back on your phone but not nearly as great on any other screen. If you’re serious about making 4K videos, buy a 4K camcorder so you know you’re using dedicated hardware instead of relying on a feature of your smartphone.