How do I know my Bluno is connected (Arduino UNO + Bluetooth 4.0)

I connect to the bluno with an android phone over blue tooth. When I connect, a little led turns on, on the board and I can now send and receive bytes over Bluetooth. I'd like to know from within the bluno program that I am now connected with a device.

For example, While connected, I can't send a new sketch to the bluno because the com port is engadged with the android device. If I disconnect from the android device, the led on the bluno board switches off and the serial port becomes available.

Any pointers would be appreciated