Rich's Tongfamily (Richtong.net add-on)

Well, the DJI Osmo Mobile 2 is an incredible stabilized mount for doing recordings at live events with an iPhone, the video quality is unbelievable and the controls are great, but the sound quality is just so, so. The iPhone has just a small monophonic microphone, so that’s one thing to fix.
Here are some solutions. The first is to get a separate stereo recorder. I have an older unit, but the Tascam. This does mean however that you have to synchronize the video and audio which is a little painful. Instead of using the standalone DJI application, you have to switch to iMovie or something.
One of the problems with the DJI Osmo Mobile 2 is that there isn’t anyway to mount a microphone and have it record directly. If you are doing low fidelity, you could use the Apple AirPods and connect it to the Filmic Pro which knows how to take stereo wifi and lay the track. This does mean that you can’t use the on-handle controls that only the DJI Go application allows so it is pretty inconvenient.
Another solution is to get rid to go tripod mount and then you can use a microphone that connects to the lightening adapter. There seem to be very few of these devices, but TechRadar, MicReviews, 9 to 5 Mac, Sound Maximum, Podcast Essentials, and iMore, all seem to center on the same microphones.
The Zoom iQ7 is a “Mid/Side” microphone array, this means that there is a center microphone and then a wider angle microphone that captures the left and right sound stage. You can then signal process it so that you can end up with a very wide stage or very narrow or even just take the mid to get monaural. This is the right design for instance with listening to music because you want to adjust things.
The Shure MV88 is a condenser microphone. This is a different technology and is best for close in interviews and recording.
Then there is the Rode iXY which is a so called “X/Y” microphone. It has two microphones that are in an X pattern, the left one records what the right ear would hear and vice versa. It is great for creating a sound stage that matches what you would hear if you were sitting in the exact center of the stage. But, you the Mid/Side is nicer if you want to balance things, so for instance if you are off axis of the concert.
Net, net, the best solution from a technical standpoint is the standalone recorder although post production is more difficult. There really isn’t a good solution if you want stabilization and great sound for right now. It is either/or.