Use method Notifier.LogInfo for debugging and logcat to check what happens
Also once BluetoothClient.IsConnected is true is will stay true also after the connection is lost. As the bluetooth protocol was designed, there is no way to detect, if a connection still is alive, therefore you have to send regularly (i.e. poll) some data to the device. And if you get an error, then you know, that the connection was lost...