Samsung's Group Play is a pretty nifty feature allowing you to use two or more phones together to either get louder sound or to make them act as the left and right speakers etc. Though the feature is a a sort of novelty and most probably wouldn't be used, it is pretty cool once you have enough compatible devices and start using it.
Now there is an alternative for those using phones from other brands and also for those using Samsung phones but on custom roms. It's called SoundSeeder. It works pretty well though the performance obviously depends on your device. The free version allows a max listening time of 15 minutes at a stretch before requiring reconnection. The full version can be unlocked via an in app purchase. Head over to the play store and xda links below and let us know here how it's working for you.
Play Store: https://play.google.com/store/apps/details?id=com.kattwinkel.android.soundseeder.player
XDA: http://forum.xda-developers.com/showthread.php?t=2392672
Now there is an alternative for those using phones from other brands and also for those using Samsung phones but on custom roms. It's called SoundSeeder. It works pretty well though the performance obviously depends on your device. The free version allows a max listening time of 15 minutes at a stretch before requiring reconnection. The full version can be unlocked via an in app purchase. Head over to the play store and xda links below and let us know here how it's working for you.
Play Store: https://play.google.com/store/apps/details?id=com.kattwinkel.android.soundseeder.player
XDA: http://forum.xda-developers.com/showthread.php?t=2392672