Do I have to install this on a window or can it just free stand/sit on a table? I’m looking for something that can read temp in another room and report to ST. Thinking about having it turn on my thermostat when it reaches a specific temp.
Or is there something better I can use?
You can have this sit freestanding.
There are other devices that can be used (and even at the same price or cheaper).
The Smartthings Multi sensor works as an open/close sensor, vibration sensor, and temp sensor. ($40)
The Smartthings motion sensor also reports temp. ($40)
There are many 3rd party motion sensors that report temp, too (such as the unbranded ones from Monoprice). (Under $25 on sale regularly)