Via PDroms

Guitarist is a virtual instrument for your iPhone.

Features:

* Unique "hammer-on" metaphor simplifies solo playing by removing the need to independently fret and pick a string.
* A complete guitar fretboard (including open strings) to the 15th fret.
* Multi-touch. Up to 5 strings can be played at once.
* Each note is a separately recorded sample, for maximum quality.
* Animated strings press down at your touch for visual feedback.
* Acoustic guitar patch included, with more options available in a later release.
* On-screen keyboard navigation allows you to easily move up and down the fretboard.
* Left handed stringing option.
* Various guitar tunings available with more to follow.

http://www.modmyifone.com/forums/showthread.php?t=63371