If your smartphone videos are sounding a little rough around the edges, the easiest way to improve your audio quality is with a wireless lavalier mic. You can scoop up a complete kit for $259 that includes a charging case, two transmitters, and receiver, a healthy discount from its usual $329 price point. DJI has made a number of improvements to this generation of wireless mic that make these even easier to use. Between the new charging case and the larger internal batteries, you can now get up to 28 hours of recording on a single charge. Audio quality has been improved as well, with two active noise-canceling levels, lossless 24-bit audio to the receiver, and voice presets that make postproduction even easier.