Stationary player from an Android smartphone. Or can you control one smartphone from the second?

Question

Android

The idea, in fact, is this. I have an old android-smart, which is idle.
I decided to adapt it for the needs of playing music. It would seem that everything is quite simple here - you hook speakers to it and go ahead - you want it from a flash drive, you want it from a network folder, you want Internet radio or stream from Google Music.
It's all just wonderful, but the question arose, how to manage it all? Every time running to smart to change the volume or switch the song is somehow not ice. I would like it to be remote. There are programs in nature that allow you to control an Android device from a desktop or laptop, but it seems to me that this is not very convenient in this case.
I would like to control music playback from another smartphone, since it is always at hand.
Google didn't tell me much about this. Can the dear community help?
I hope I have explained the problem clearly.
Thanks in advance!

Answer 1

Why so difficult? Why don't you want to transfer the device itself with the player? I have an ipod connected to the speaker via bluetooth and is in my pocket.

Answer 2

https://play.google.com/store/apps/details?id=com....
there are also under linux and under Windows, don't know about poppy