On this photo posted in instagram, you can clearly see the Traktor Kontrol Z1 Mixing Controller. If compared with this official picture from almost the same angle: http://www.native-instruments.com/en/products/traktor/traktor-for-ios/traktor-kontrol-z1/ , you can tell that they are exactly the same.more
Plug this in to your ipad and voilá! Rock that house party with a professional dj setup. With the ability to cue the next track as with normal DJ gear, and with the effects available at the touch of a dial, you really can mix it up at your next gig. Super portable, super sounding, super cool product.
I use this with Traktor for DJ-ing and recording mixes. Very compact, high quality, works great! Probably a bit limited when used by itself if you get into remixing and production, but that is easily remedied by adding an F1, X1, etc.