AudioLayer satisfies the most sought after gap for contemporary music production on iOS devices. AudioLayer is a full featured open standard audio multi-sampler pushing the boundaries beyond what has been available even in the desktop music production worlds. And all this integrated in all relevant iOS production environments especially the emerging AUv3 AudioUnit standard.
Original Soundfont by John Nebauer
The Steinway is from Anthony Deaton.
The Salamander Grand made by Alexander Holm.
The acoustic steel guitar was made by Keith Smith.
SSO Strings is a creative commons licensed library.
Other sounds are the pick of the best that are freely available on the net.