Hi, this is a simple Android app that allow people to listen to music together via wifi. It works without Internet access, for example you can use wifi hotspot. You can use it as an ordinary music player as well. This is my first app and it is a BETA, for example that's why the music doesn't sync perfectly among devices, but it is optimal for headphone use. It is based on nanohttpd library and tcp socket.
Firstly Download apk and install. (Android 8.0+) Tap onto the settings icon and start the server with the button. On the other other device tap to the Client button and than write the server ip into the textbox and connect.
P.S. It's open source, you can use it as you want.