I have Nest thermostat and a Nest camera. Thermostat is in the hallway and regularly thinks nobody is home. Camera knows I'm home because of movement (or I should be able to show it how to tell). But the Camera doesn't talk to the thermostat.
You create a dependency when devices connect to the Internet and you may give up some privacy. In return I assume you'd get some intelligence and integration.
My #1 issue my Nest is that my house is always freezing in the winter because it always thinks I'm not home as I might be home but not necessarily walk in front of the thermostat routinely. Hence it switches to "Auto Away" mode.
It would be nice if the Nest app I had on my phone could identify that I'm home (i.e. am I connected to my home WiFi network, or check my location via GPS) and then communicate that to my thermostat.
I saw an app on the play store a while back that did exactly that. It worked with the nest API and your phone, you said what wifi's and what areas and it pinged the nest to keep it in home mode.
It's called Away Smarter on the google play store.
We gave up on the auto-away stuff and use the Skylark app on our phones, which does geo-fencing. I agree that this should be a built in function of the Nest app, but a five dollar app as a workaround isn't too bad.
My SmartThings supports a smartphone geo-fence to detect presence and an NFC fob if you don't want to link a phone. I don't understand why my Nest can't do that too.
I get the feeling that Nest has transitioned from innovation to revenue.
You create a dependency when devices connect to the Internet and you may give up some privacy. In return I assume you'd get some intelligence and integration.