Right now if the app is connected to the SD and the SD shuts off it takes a minimum of 5 seconds to detect the loss of connection - due to the android subsystems connection management settings. Potentially the bluetooth devices can communicate to lower this interval or other techniques can be used to detect disconnect instead of relying on the android subsystem. (e.g. no packets received within X seconds, new control messages added to the SD bluetooth code, etc.)
Right now if the app is connected to the SD and the SD shuts off it takes a minimum of 5 seconds to detect the loss of connection - due to the android subsystems connection management settings. Potentially the bluetooth devices can communicate to lower this interval or other techniques can be used to detect disconnect instead of relying on the android subsystem. (e.g. no packets received within X seconds, new control messages added to the SD bluetooth code, etc.)