Using the speaker, you can tell the Project Nursery camera to pan and tilt, play a lullaby, check the temperature in the nursery and more. You can do all this from any room that has an Alexa-powered speaker, so that you don't need to enter the nursery and risk waking up your sleeping baby. If you already own an Echo speaker, Project Nursery sells the Alexa-enabled camera on its own.
It really depends on what you feel most comfortable with. There are audio monitors that allow you to listen to any noise coming from the nursery, vital monitors that track sleep and breathing and video monitors that add sight to sound. Babylist parents overwhelmingly choose video monitors. The security of seeing what your child is up to—like if they’ve gotten tangled in their swaddle, pulled their diaper off or climbed out of the crib—can be worth the extra cost of a video monitor.