I would think that any microphone with an 1/8″ jack would work. The headphone jack on the iPod/iPhone supports earbuds that have both a microphone and headphones in them.

Nice job.

I’m not sure about on the iPhone 4, but on the iPad you can use the camera connection kit and use a quality USB mic.

Of course, if you really want to go high end, there’s a special one by Blue Microphones:

http://www.bluemic.com/mikeyforipod/

You will have to excuse my exhuberance of my post regarding this book. You have to understand that I come from a church that has the LSB but it does little more than sit in its holder in the pews and look pretty. We use it only to sing the hymns out of it on traditional service Sundays (and then, more often than not, some of those are printed in the bulletin as well), but we print most of the divine services in the bulletin on those weeks and so, they don’t get used. I’ve been told we put the divine services in the bulletin because it is felt it is easier to use the bulletin by visitors and the LSB is too formal and confusing for visitors and non-members. I’m excited to see a book like this because it is something we can put in the hands of those unfamiliar with why we practice the way we do and they can hopefully get a better grip on what we believe and why we believe it. I say kudos to the team that put it together and I, for one, can’t wait to give it a read when it arrives!!