Get alerted if your refrigerator door has been left open for too long! The FDA says that your fridge should be set between 38 and 40 degrees fahrenheit. If the temperature rises above this temperature for an extended period of time, your food could go bad. Prevent this from happening with the littleBits smart fridge circuit. We've all accidentally left the fridge door open. Now your fridge will communicate with you when this happens so you can save your food!