Recording with your iPhone's built-in microphone is a quick and easy way for musicians to sketch out song ideas. But if you're really bent on transforming your iPhone or iPod Touch into a mobile, multitrack recording studio, you'll need to drop some money on a quality recording app, and some kind of adapter for connecting instruments or mixers.
Professional, affordable apps such as FourTrack and FiRe recorder solve the first half of the equation, but shrinking a professional audio interface down to a pocketable iPhone adapter is a tall order.
Fortunately, the folks at Sonoma Wire Works are working on one of the best solutions we've seen yet. The GuitarJack ($199) is due out this fall, and offers a 1/4-inch instrument input, stereo line input, and headphone output, all in an adapter that fits in you palm. More importantly, the line and instrument inputs offer selectable gain pads, 60dB of continuous analog level control, and can be separately assigned for simultaneous dual-mono recording.
Construction quality is above and beyond any iPhone recording accessory we've seen, including a casing made from anodized aluminum, and a 1/4-inch input from Switchcraft made from a nickel-plated brass. The standard 30-pin iPhone connection is guaranteed to work with the first- and second-generation iPod Touch, iPhone 3G, and iPhone 3GS, but will not work currently with the Apple iPad, iPhone 4, or other iPod models.