Here is a very simply tip for medical students who carry smartphones in the hospital: carry an external battery pack in your white coat pocket so that you can charge your smartphone. Inevitably, your smartphone battery will go low. You may be looking for a USB port or power outlet to charge your phone, but then you may quickly get called off to see a patient or attend to a Code Blue emergency in the hospital. It's not worth leaving your phone plugged in somewhere.
Keep the battery in your pocket. If your senior resident needs a quick charge, you'll quickly become a hit by offering an easy way to recharge.