Given the absurd and idiotic behavior reported by users of the NEST and NEST 2 thermostats, I took one look at this smoke detector's webpage, saw who made it, and basically said "nope" and closed the page.
Thermostats that generate enough of their own heat during operation that they sense the temperature being up to 10 degrees warmer than the room, multiple reports of them not coming on at all in 'vacation home' mode where owners will use them to keep pipes from freezing, oddball lockups that leave houses baking/freezing, etc.
This is in addition to the cloud-only BS way of changing settings.
PISS poor quality control is the only answer I have for the thermostats' behavior.
I can't wait for the smoke detector to just decide not to work, to detect everything as smoke and alarm constantly, or to detect the licking flames as a handwave and disable.