Related projects

EasyH10 is an open source project for the development of a software suite for iRiver H10 digital audio players. This is the ancestral project of PMPlib.
libitunesdb is a library designed to make it easy to access the songs and playlists stored on an iPod. libitunesdb was originally based on gtkpod iTunesDB parsing code.
An implementation of Media Transfer Protocol (MTP) (developed by Microsoft) in the form of a library suitable primarily for POSIX compliant operating systems. Refer to their web site if you have an MTP device because PMPlib project will not support MTP devices.
Newer libgphoto2 versions also support Media Transfer Protocol (MTP) based media players since their communications protocol is based on the Picture Transfer Protocol (PTP).