Microphones

The built-in microphone on your device may do just fine.  But for best results, I recomend you use a good external microphone.  USB microphone are fine for these purposes.  Here are some that I have used that worked well:

Advanced Setup

If you want to use additional inputs such a second microphone or a pickup on your instrument, you will need an audio interface device.  Chip Bach recommends:

If you are using a device such as pad or smartphone which lacks the requisite connectors that you need.  Look for a powered USB hub and/or an "On-the-go" (OTG) device.

For more information about these kinds of configurations, see Chip's article "Keep on Picking".