We use wireless printing through a COM port over BlueTooth. Having BlueTooth on all of the time can contribute towards energy consumption and cause the battery life on the Pocket PC to deplete faster. Now I disable BT when the application starts, and then re-enable it to print and disable it immediately afters. This adds about 1 second to each print job but it should save the battery power.
private static extern int BthGetMode(out BlueToothRadioMode dwMode);
private static extern int BthSetMode(BlueToothRadioMode dwMode);
public static BlueToothRadioMode BlueToothRadioMode
if (value != BlueToothRadioMode)