Here is a great NYT’s piece on how Nextdoor can be used.

http://mobile.nytimes.com/blogs/well/2015/10/13/meet-the-neighbors-theres-an-app-for-that/

“What Nextdoor does better than other social networks like Facebook or Yahoo Groups is fill a void that technology has left in the communities where we live. With so many of us depending on email, cellphones and social networks for interaction, we often neglect to get to know our neighbors. Rather than become a place to share vacation photos or cat videos, Nextdoor is more about utility.”