The first day I used Google Now, my phone buzzed to tell me I needed to leave in 15 minutes for my restaurant reservation, because there was traffic on the way.

The thing is, I had never told my phone I had a reservation. Or where I was, or the route I planned to take. Google had spotted the OpenTable reservation in my Gmail in-box, knew my phone’s location and checked Google Maps for traffic conditions.

I was creeped out.

Claire Cain Miller.