I was answering the question of "What is the business of the Facebook SDK doing in a thermostat app?". The though process is "Want to offer Facebook Login for

I was answering the question of "What is the business of the Facebook SDK doing in a thermostat app?". The though process is "Want to offer Facebook Login for Nest" -> "Need to use SDK for it" -> SDK talks to Facebook servers. I have never used the facebook SDK (and have not used the Nest App in a long time) so I don't know personally.