[NEEDS UPDATING] Bulbs, switches and sensors, oh my....what to buy (device class features FAQ)

[JDRoberts]

Adding a discussion thread specific to humidity sensors:

Temperature and Humidity sensor, which one which you recommend?

Hi all, Newbie here. Going to move to in a few weeks and I would like to have a few area monitored. I start reading about Smartthing. Specifically I want to know about the attic temperature and humidity and also the same for the basement, what sensor(s) is good for this purpose? I found the Aeotec and Zooz multisensors on Amazon. But there are quite a lot of devices out there. Where else would you recommend to source the sensors? May be there should be a list of supported devices by type and popularity? Thanks Will

And one just for temperature sensors:

Recommend a temperature sensor? (2017)

Can someone recommend a reliable temperature sensor that can be used with SmartThings? The “Works with SmartThings” page doesn’t let me narrow the search down to just sensors that report temperature. Why? you might ask … I’m done with my SmartThings multipurpose sensors. The temperature here hit a whopping 80 (Fahrenheit), and 2 of my sensors are now showing as “unavailable” in SmartThings (a third is intermittent). The last reported battery strength was 89%. I happened to have two new CR2450 batteries around (Panasonic of course), and that has not fixed the problem. In one there is so much play when the battery is inserted you have to push on the battery to make it contact. I had to bring both sensors closer to the hub to get SmartThings to see them, and they have dropped off again no…