We first decided to check out Guitar Toolkit ($9.99, available here) because we recently bought an acoustic guitar and we needed a way to tune it. The tuner that comes with Apple's GarageBand was having trouble hearing our notes, even with a reliable microphone, so we turned to the iTunes Store for help. Guitar Toolkit's digital tuner makes quick work of adjustments: it heard our notes perfectly and had us strumming in tune in under a minute.

There's much more to Guitar Toolkit, however, While there are several guitar tuners available from iTunes, none of the others offers the range of useful information you'll find here. The app offers an easy-to-navigate chord library that shows us just where to hold our fingers for over 1,500 chords.

It also has includes a metronome that supports time signatures (by providing a different sound for the downbeat of each measure) and offers a flash interface if you'd prefer quiet help. While we've been using it with a standard six-string guitar, the app can also be set to tune 12-string guitars and 4- and 5-string basses.

It's not just a tuner, but a powerful guitar resource and it's handy for this beginning player (or guitar gods of any level) to have on hand.