I think you just described ROCKI! - http://www.myrocki.com/ http://www.myrocki.com/ They had a successful Kickstarter in 2013 (https://www.kickstarter.com/proj

I think you just described ROCKI! - http://www.myrocki.com/ http://www.myrocki.com/ They had a successful Kickstarter in 2013 (https://www.kickstarter.com/projects/rocki/rocki-wifi-music-system-from-every-phone-to-all-sp https://www.kickstarter.com/projects/rocki/rocki-wifi-music-...) and went through Techstars Boston in Fall 2014.