Meet the Owlet Smart Sock 3 Monitor: a smart wearable oxygen and heart rate monitor for babies that helps you keep a close eye on your child’s health. It combines with your iOS or Android device to give you a 7-day view of trends. The sock can be charged wirelessly. It has a battery life of up to 16 hours.
This smart sock can measure total hours slept, number of wakings, and sleep quality. It uses pulse-oximetry technology to get the job done. You can find out more about it here.