Tasker - Tasker is an application for Android which performs Tasks (sets of Actions) based on Contexts...
Spotify - Map shows when two people play same song at same time
AutomateIt - Automate Your Android!
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
Automate - Automate various tasks on your Android smartphone or tablet.
SoundCloud - Enjoy music & follow favourite artists