The Rule of Three Trilogy by Eric Walters

The Rule of Three Trilogy was written by Eric Walters and published by Farrar, Straus, & Giroux.

1.  The Rule of Three, 2014
2.  The Rule of Three: Fight for Power, 2015
3.  The Rule of Three: Will to Survive, 2016

Publishers summary:

One shocking afternoon, computers around the globe shut down in a viral catastrophe.  At sixteen-year-old Adam Daley's high school, the problem first seems to be a typical electrical outage, until students discover that cell phones are down, municipal utilities are failing, and a few computer-free cars like Adam's are the only vehicles that function. 

Driving home, Adam encounters a storm tide of anger and fear as the region becomes paralyzed.  Soon—as resources dwindle, crises mount, and chaos descends—he will see his suburban neighborhood band together for protection.  And Adam will understand that having a police captain for a mother and a retired government spy living next door are not just the facts of his life but the keys to his survival, in The Rule of Three by Eric Walters.

This is an interesting take on the apocalypse plot.  Typically, post-apocalyptic stories begin with total mayhem and immediate killing sprees within the early pages of the story.  The characters end up on the run, eventually finding an oasis in some distant part of the country, where they can finally regain a sense of normalcy.  Sometimes the oasis falls, and the characters must try to find somewhere else that is safe.

In these books, Adam's neighborhood is the oasis.  We follow their story as they build a safe haven and defend it against the outsiders who try to steal what they have.  Since Adam and his acquaintances are never on the run, the plot is rather slow for much of the first book.  It gradually becomes more interesting as complications and threats develop.

Since the book doesn't open with instant mayhem, it is more realistic than many of these types of stories.

Overall, this is a very good trilogy.  It does drag at times.