Spotify - Map shows when two people play same song at same time
CopyTrans Manager - CopyTrans Manager: The free iTunes alternative to manage iPhone, iPad and iPod without iTunes. CopyTrans Manager allows you to quickly drag and drop music and videos from PC directly to your iPhone, iPod or iPad.
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
iMazing - iMazing lets you transfer music, files, messages, apps and more from any iPhone, iPad, or iPod to a computer, Mac or PC. Manage and backup your iOS device simply without iTunes. (was DiskAid)
SoundCloud - Enjoy music & follow favourite artists
WALTR - Drag-and-drop any media file to an iOS device (without iTunes) for native playback.