I bought one of the speakers yesterday to play around with.
To clarify, it's only a speaker, sounds not included. From the video I "assume" the BlueRail app has sounds as well as control programmed into it, or is the sound coming from the module inside the engine?
The speaker button not only turns on/off the speaker, it also is used to increase the volume.
It requires a micro USB charging cord that's not included.
I sat it on top of the tender on my BPRC RailKing 2-8-0 and initial tests tell me it's not loud enough to overcome the noises an O scale train makes going round the track, but I'm still playing with it. What I was doing was playing a Youtube video on my ipad thru the cube speaker as it ran around the layout. Could have been the quality of the video.
Hopefully BlueRail will do us o-scalers right with a robust setup.