YOU HAVE GARAGEBAND ON your iPad, and want to record a guitar part. Or you have a great idea for a riff, but the only electronic device around is a smart phone. Fortunately, there are easy ways to interface your guitar to your mobile pet brains.

The least expensive (and generally smallest) interface provides impedance- and level-matching, and then goes into the device’s audio input—the approach taken by IK Multimedia’s iRig and Peavey’s AmpKit LiNK. The tradeoff is that the signal is subject to any limitations in the mobile device’s onboard preamps and converters. Frankly, most of these have pretty decent audio quality, but to move up one more level, check out interfaces that convert your guitar signal to digital data that bypasses the target device’s analog electronics for an all-digital recording chain.

Employing quality preamps and converters ups the price, but products like Sonoma Wire Works’ GuitarJack are designed specifically for exceptional fidelity with guitar or bass. Even Apogee Digital—known for high-end pro audio gear— has gotten into the act with JAM for iPad, iPhone, and Mac (it’s also compatible with the adapter needed for the iPhone5 and iPad Mini). At $99, JAM is highly affordable, yet it provides a quality digital feed into mobile iOS devices, and it works with active or passive pickups. Keep one of these puppies in your guitar case, and you’ll never lose an inspiration again—as long as you have your pet brain with you.