Shooting with an iPhone is super easy, and the iPhone has an amazing camera and some manual settings that make it easy to get great looking shots. There are plenty of editing apps, including Apple's own iMovie for iOS, that are just as powerful as the desktop equivalents, and you can share right from the phone to your favorite platforms.
This makes the device ideal for video journalists and producers who are always out shooting and like to turn their work around quickly.
One obstacle when shooting with an iPhone, however, is audio. The internal mic on the iPhone is designed for phone calls, not for video, so it can sound distant and hollow. There are many mics that you can buy for the iPhone, and now Sennheiser, one of the most trusted brands in audio, has made a mic specifically for your iPhone, the FOCUSMIC Digital.
The microphone is a directional shotgun that can be adjusted 270 degrees so you can use it in selfie more, or for your rear-facing camera, and in between. The microphone attaches to your iphone via a clamp, and can plug directly into the phone using a lightning cable. Since most new iPhones only have the lightning port, you won't be able to monitor the audio while shooting, so make sure to test it out before hand.
This is a great option if you are looking to get better audio on your shoots with your iPhone, and can be a small addition to your mobile kit. You can pre-order the FOCUSMIC here.
Check out this video from Cinema5D: