Money (I don’t have much, but I can save up)
Do that, always good to save up.
-How good is the sound quality with a splitter cable?
Same as the sound quality of the iPad just mono, so no stereo effects will work.
-Is there such a thing as a “reverse Y cable” (so I can hook the Z1 up to my iPod speaker)?
No.
-I only have iOS 6, so using a controller with djay 2 is not an option (besides, none of them have line faders)</p>
Upgrade to iOS7 its free. Yes there are plenty DJ controllers for djay that have line faders… (who gave you that thought???)
-How are the features on Traktor DJ vs. djay 2?
I feel that djay in the iPad is more complete than Traktor. Traktor has some very good things going for it so it might beat djay on the iPad in the future, but at the time of writing this I feel that djay is the less complicated and complete featured program on the iPad.
Actually the most fun controller for djay and the iPad that I have had in my hands was the Pioneer DDJ-WeGo2. The built in iPad stand holds up, it has the connector cable built in and it has its own soundcard with superior sound quality. So if you save up, I would consider this. It is still far from a thing that I would use professionally as the iPad software titles in general are not there yet for pro use, but even doing your house or birthday party with this setup is easy and fun.