Hearing Music with friend in facebook

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My friend tell me that there is an apps that can make us listen music together on facebook. It connect trough facebook chat, and we can hear the same mucis, at the same time, together while chatting. My friend also hear it somewhere on the internet and never found out how to do that. Did anyone know how to do that? And will it cost money to add the apps? My friend only got the picture ( which i am upload ) as the only clue about this apps.