Please read this article for background/more info: iPhone/iPad external microphones

I am now pretty confident in my portable video/audio recording solution using my iPhone 4. Everything I need to do on-the-spot interviews, B-roll filming, and even more advanced shooting, I can fit in my iPad's bag.

Here's my basic setup - everything I need (with the exception of the iPhone 4), I put together for under $100:

• iPhone 4 Tripod mount + mini Targus tripod ( here's how you make the iPhone tripod )
• External Lavaliere microphone + adapter for iPhone 4 ( here's what I'm using, along with some samples, and microphone recommendations )
• An interview mic setup - so far not ideal, but getting there ( a Shure SM58 with the iPhone 4 )

This setup is ideal for interviews, recording video podcasts, and, with the help of another DIY project on which I'm working, recording video with some interesting perspectives.