What's the latest inside poop from the Internet of Things, which has already brought us smart TVs, smart appliances and smart thermometers? A smart baby-changing pad. The Smart Changing Pad connects with an app so new parents can track their child's weight, sleep and even the number of diapers they use. It's debuting Monday at the ABC Kids Expo in Las Vegas, made by a start-up called Hatch Baby, which recently raised $7 million in early funding.