We have an external device (it's not android) that we usually connect to PCs via Serial Port->USB converter. But now we want to use also Android tablets to send commands to that external device so we are going to add a bluetooth module that can act as a bridge between the device's Serial Port and Android tablets.
Should we buy a slave bluetooth module or a master one?
The external device is like a "server" that is always working, and the PC/tablet just connects and sends commands to it.
Master means "server" or "client"? It's a bit confusing cause the Android doc uses "server/client" terminology while hardware stores use "master/slave".