Secret Base Design just released VoxKit! This Universal app is a MIDI Drum controller than you can trigger with sounds you make in the real world. Different sounds can trigger different drums! You can then send the MIDI out via CoreMIDI, or even DSMIDI WiFi. If sending MIDI all over the place isn't your thing, VoxKit has its own sample playback engine that supports Audio Copy/Paste.
Some people have been comparing this to the best part of the Wavedrum Mini, at 1/250th the price! They are also doing a sale on their other apps, Audio MIDI Connect and Live Guitar are both just $2!