Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.
Download on the App StoreAudiobus is the app that makes the rest of your setup better.
Comments
Preamp is needed
Thanks, that was a quick answer.
you'll need a preamp in any case for a turntable pickup is a very impedance critical part.
Fortunately those preamps (that also correct the modified frequency response of the vinyl cut) are not very expensive - to achieve reasonable results. I used a Project Phonobox once, which was only slightly below a NAD Preamp.
You could spend a tremendous amount of cash in such gear ...
If you have a DJ mixer, you could just run the turntable through that and use the line out to feed the iPad.