I'm trying to use an external mic with my Droid Razr. I'm trying to do a video setup where I have sony video camera recording me and I want to use the Razr as a audio recording device. Can't I just install an external mic in the headphone jack? If not what can I do? Iphones apparently make this very easy. I need a CHEAP solution. Thanks Antonio P.S. I also have a Droid HTC Eris. Can the Eris record audio like this?