Re: Call me old fashioned
But a smoke alarm (tested monthly) on each floor for when your in, and home insurance for when your out is more reliable that nest!
Precisely. Although (nearly) weekly is my schedule - check the print on your alarm and don't assume. I'm lucky in that I'm over six foot tall and can just reach the test button. Takes less than a minute of my time per week. Two smoke detectors, mains wired and battery backed - one each per floor, centrally.
Fire safety needn't be a big deal, nor cost a fortune. I have two dry water mist fire extinguishers (*) - one per floor - £88 total, should last about three years or so before needing recharge or renew. Fire blanket for the kitchen - £13. Escape ladder for upstairs out of window - £38.
Take the possibility seriously for a couple of hours thought (do a little risk assessment) and then a casual inspection every now and then. Perhaps buy a few things that will probably never be used, but will be really handy should the worst happen. Just do it.
How much is a Nest thingie again? I'm a nerd (and a IT consultant) and love gadgets but I'm also a fire safety bod for my company. At home I keep it low tech, comprehensive and cheap. Please do the same.
(*) Dry water mist - pretty new idea, recommended by our local Fire Safety Officer from the Fire Brigade. Pressurized water in nitrogen - comes out atomized and not "wet". Works for nearly all fire types found in the home. Safe for eleccy fires, basically use where foam and CO2 are indicated.