Use FourTrack with a headset/mic to better hear existing tracks while recording a new one.

Sonoma Wire Works will sell some Four Track downloads just based on its alluring design, but this beauty's got brains. This four-track audio recorder's smart layout utilizes every square centimeter of screen space without resorting to controls that are too small to operate.

Musicians and songwriters can record four separate audio tracks of unlimited length, one track at a time. Upon playback, you mix their levels with the faders, and pan them left or right. A shuttle wheel moves backward and forward within the song, and a timeline lets you instantly skip to a point in the song, which helps tremendously for any song of a minute or more. Press a track's record arm button and then move the record slider (which helps prevent accidental track overwriting) to record. The Song drawer lets you name the song and see the song list, where you can create as many songs as available memory allows. A Wi-Fi sync feature lets you download the individual, CD-quality tracks to a computer from a Web browser, where you can load and edit them in music software such as GarageBand. That's especially imporant for anyone who wants to use their FourTrack projects as part of, or inspiration for, more polished recordings.

With decent audio quality, nice features, and smooth operation, FourTrack stands out among App Store music programs. It could benefit, however, from adding a metronome, audio effects, and an overdub option for layering tracks. Overdubbing would mix a new recording into a recorded track, rather than overwriting portions of a recorded track, which is what FourTrack does.