I am not a professional guitarist. Like many of you, I can fake my way through a few chords and song melodies, but I couldn't play you any "tasty licks" or shred your face with my epic guitar wankery. I'm a hack, and I'm comfortable with that.
Humble skills aside, I do enjoy picking up the guitar at least a few times a week--just for fun and to keep up what few chops I have. My big problem is finding a way to play guitar without aggravating my wife, or waking my kid. I have an amp, but it doesn't have a headphone output. I have a slick JamVox USB soundcard for my computer, but the setup is a bit involved for just messing around and it's not exactly portable.
When I heard about AmpliTube iRig, a $39 headphone adapter and free app that works with the iPhone, iPod Touch, and iPad, I knew I had to check it out. The premise seemed simple: an adapter for plugging in your guitar and a pair of headphones; and an app that runs emulations of guitar amps and effects, which you can tweak to your heart's content. Best of all, the whole system is compact enough to fit in your pocket, provided you aren't using it with an iPad.
The results are decent. I have a full review of IK Multimedia's AmpliTube iRig system over on CNET, which includes a short sound demo I recorded, comparing it against my $120 JamVox USB soundcard (not the fairest test, arguably). Sure, iRig is a bit noisy, the overdrive is brittle, and the reverb isn't very spacious--but it's still relatively astounding for something that fits in your pocket. In the coming months, I'll try and see how it stacks up to similar products, such as iShred Live and PRS Jam Amp.