SoundSeeder

SoundSeeder is an app that lets you sync different devices through the same Wi-Fi network, so they work as speakers for your Android. This means that all devices you connect will play music at the same time, as if they were just one speaker.

You can easily play all the music on your device with SoundSeeder, but you can also use other services, like online radio players or Google Play Music. Creating playlists within the app is also very easy.

This free version has two very important limitations. The first is that instead of connecting as many devices as you want, you can only connect two. And the second limitation is that you can only play 15 minutes of uninterrupted music. If you want to connect more devices, you will have to buy the full version.

SoundSeeder is a very useful app for parties and other social events, as it basically lets you sync all devices that can play music so that they work at the same time.