I used to have the original iRig, which sounded OK, but if I ever moved my iPod or the iRig it made a lot of noise. What do you guys think is the best interface to plug a guitar into an iOs device now? I use Amplitube and Jamup...
Apogee Jam is the highest quality, hands down.
Telecaster - SG - Jaguar
Princeton Reverb, Extra Reverb
P-Bass - Mustang Bass
Apogee Duet 2 - Ableton Suite
Buy the rocksmith cable and use the camera adapter. I did this on my iPad2. I haven't tried it on my Air yet but I assume it works.
Line6 Mobile POD app and Mobile In cable. Once you have the cable you can use just about any app. Mobile POD has tones of amps and effects. Nothing more to buy. You can download even more tones from The Line6 website.

Most of the others charge you for the add on popular/useful effect and amps regardless of how much they charged you for the app to begin with.
--- Joe ---
77 Bradley LPC || 07 PRS CE22 || 11 PRS MC58 Artist || 95/02 Fender Strat || 99 Gibson LP DC Std Lite
06 Ovation Elite-T || 12 Martin GPCPA4
Boss GT100 || Peavey Stereo Chorus 400 || Peavey Bandit 75 || Roland JC77
Thanks everybody. I'm actually thinking of getting Rocksmith for Christmas for the kids. Time to motivate them to play the guitar!

I guess since I have a Pod X3 the Line6 interface makes sense...