Rather than buy a mic for the iPhone, I bought this adapter that lets me use any dynamic mic I already have, such as the Shure 57's, 58's Telfunken M80.
It has a TRRS connector for the iPhone and goes to a female XLR connector and headphone jack.
You can get them at Amazon.....
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I'm planning on using the Telefunken M80 for recording as it gives a nice crisp clear sound. I just ordered the adapter tonight, so I don't have any samples for you. The mic on my iPhone 6 Plus doesn't sound too bad....I do have a sample of that here...…
https://www.youtube.com/watch?v=mPMr...GxYWiv8snDmQjw