I've used the Tascam iM2 with a lightning pin adapter and can confirm it works and can recommend the iM2.
A tip. If you can't get the recording to start in stereo, turn your iPod off and on again, so you'll want to start recording 5 or 10 minutes before the show starts in case you need to do so. I believe this is a problem with the app I was using, not the mic, but just so users know.