[aftbit]

I also haven't found anything commercial in this space. Luckily it is a pretty easy and cheap (<$10 in parts) hack project.

I made a thermometer/barometer/hydrometer using an ESP-8266 wifi microcontroller ($5 on ebay) and a single BME280 sensor ($1 on ebay). Plugged into one of my left-over old 500mA phone chargers, it makes a wireless indoor weather station that speaks HTTP.

I bought the sensor on a breakout board, soldered a couple of wires, flashed micropython to the ESP-8266 (NodeMCU), and wrote wrote Python to POST my server with the temperature data, schedule a wakeup, then go to sleep.

But as you say, it took me a weekend of hacking around to build. This seems like exactly the kind of thing that should be available for $10 on eBay yet I can't find anything at all open.