If you are thinking of starting a podcast then the iRig Mic is an ideal means for you to capture audio in an easy and quality way. It will plug into both iOS or Android smartphones and provides a uni-directional mic which makes capture much more precise than when using the built in microphone.
Importantly the iRig has a dual mini-jack which allows you to plug in a pair of headphones to monitor your audio in real time. This feature only works with certain apps, one of which is the iRig recorder which can be downloaded from the app store.
In our tests we have found that the 3 level gain switch is always best left on the most powerful setting. Made of metal the build quality seems good, the lead is long enough for most applications and the sound quality is perfect for podcasting. Interviews become possible in busy environments where otherwise the audio you want would be swamped.