Question

want to connect to device and start receiving data from the external device
now able to list devices and pair to that …..now wish to connet to it and start receiving data from it

Is there any way because i dont exactly know wat kind of data it is sending 
means in which formate etc ...

that is Bluetooth device is continuously sends data to app so the app should continuously receive data

Answer 1

use listenUsingRfcommWithServiceRecord instead of
this code in service

Method m = device.getClass().getMethod("createRfcommSocket", new Class[] {int.class} );
            btSocket = (BluetoothSocket) m.invoke(device, 1);