The Nanit Smart Baby Monitor ($249) does it all: takes HD video and photos (with zoom); tracks sleep and provides personalized sleep tips based on your child's sleep; has temperature and humidity sensors, night vision, and a nightlight; and, best of all, is Amazon Alexa integrated. With Alexa, you can ask how your baby slept last night and what time they woke up, or inquire as to how many times you stumbled in and took them out of the crib to soothe them — all so you can figure out how to get baby to sleep better so, in turn, the whole family sleeps better.