Sonoma Wire Works announced the launch of FourTrack, a multitrack audio recorder for the iPhone and iPod touch (2nd Generation). FourTrack is a songwriting and practice tool for singers, guitar players, piano players and other musicians who want to capture musical ideas and record songs on their iPhone. Plug in a microphone, arm a track, record, and repeat. FourTrack works with the iPhone built-in microphone, a headset mic, or an iPod touch with a third-party mic and headphones.
» App Store – FourTrack

After bringing us iPhone video recorder, Dreamcatcher has created another useful app. iPhone Recorder is a powerful sound recorder specially made for iPhone. It can record sound as mp3, m4a(ringtone required format) or aac on the fly, so you may record audio to ringtones directly. The recording is space saving, all-day-long high-quality recording will be a file as small as 0.5G. iPhone Recorder supports intelligent recording volume dynamic adjustment algorithm which guarantees better recording performance . » iPhone Recorder 1.2.1