Jerry is making instructional videos and wants the audio to come through his bluetooth headset while recording it so he can do wirelessly. Leo says that the Bluetooth earpiece profile is only phone quality and that's not what he'll want to record quality audio. Leo advises recording to the iPhone via a lapel mic that's plugged into it. Or, he could try a Wireless system like Audio Technica. It would work great as long as he doesn't get a lot of RF interference.
Pranav is a musician who wants to record some love songs using his iPod. Leo says that he can do that using Garage Band. He's interested in getting a higher quality mic, though. Leo says that Apogee Electronics has a studio quality microphone, called the MiC. It has a 30 pin connector with digital recording support.
Leo says Laura needs a camera that accepts external audio like the Canon Vixia. She can then plug the mic in. If Laura needs wireless, then the price goes up, and cheap wireless is a bad idea. Leo uses Lectrosonics for wireless microphones. They're very pricey ($1000 per mic), plus the receivers, plus the mics.
The problem with using the camera's internal mic is that it picks up motor noise from the camera. When shooting video on a DSLR, Leo recommends using an external mic that can plug into the mini-jack on the camera. Leo uses an adapter from Beachtek that he can connect to the camera so that he can plug in professional microphones.