What can you do if your perfect production is made a little less perfect by some lousy audio? Very often, an actor’s lines will be unusable because of extra noise, background sounds, or a variety of technical glitches. But, don’t despair. You can easy replace that bad dialogue with the help of your iPhone, and we’re going to show you how. This tutorial also demonstrates the use of the FourTrack recording app, and an external mic named Mikey.