4. I also wish the Nest Hello used facial recognition a little better. There's no way to exclude certain individuals from triggering a notification when they're recognized, for example, and I don't need the app to tell me that it's me who just arrived home. MORE: Amazon Cloud Cam vs. Nest vs. Ring vs. Netgear: Who Has the Best Camera Storage Plan?Also, to use Familiar Faces, you have to subscribe to Nest Aware, which starts at $5 per month. That subscription enables additional features, which we'll go into later. Other FeaturesThe Nest Hello can detect people, motion and sound. You can't adjust the sensitivity of the sound detection; it's either on or off. I got notifications of birds chirping first thing in the morning, when the neighborhood was otherwise quite quiet, but I didn't get notifications throughout the day about every car that went by.