Recording great phone video means capturing great audio too — Samson's Go Mic almost does it perfectly.

As a mediocre musician and an even more mediocre comedian, I often like to record myself for both posterity's sake and to learn from my many, many (many) mistakes. The built-in microphones on most smartphones nowadays are decent, but a quality external mic can make the difference between a good recording and a great one. If you're shooting phone video, and shooting in 4K at that, then you should have clear audio to go along with it.