Listening to music together

[Robinko]

Hi. I've made an application for me and my girlfriend that allows listening to music together.

Basically there is just 1 button called "Play together". After start, the first person is the "Host", and sends the actual track, track position if changed, and play/pause state to the server. "Client" just receives it and changes his values.

Screen 1

Screen 2

I'm wondering if there is any legit and free way to listen to music together like this 🙂

I think I wouldn't be able to make it with API, because some of those functions (like "seek") are not available for free.