Syncing iOS content with iTunes is one-way ticket and you have no option to manage your iOS content as the way you want. SyncBird comes as a game changer, which allows you to transfer your music, photos, videos and all your iOS content between any of your iPhone, iPad, iPod and Mac computer.
Synchronicity - Compare music libraries with your friends
Songlink - Share music with anyone.
AnyTrans - AnyTrans is an ultimate product manager that converge your entire apple products and consolidates every access to all your content in one place including video, audios, images, messages, voice memo etc.
humit - A social networking app for music sharing and discovery.
SynciOS Manager - Syncios is a free yet powerful cellphone to PC transfer software which can help to transfer App, Music, Photo, Video and Ebook from PC to iPod/iPhone/iPad as well as Android Phone, Android to PC, iPhone PC and iPad to PC.
aux.app - A free web-based music platform to play music from other popular online streaming services.