For our final project in Connected Devices, we were tasked with creating an IoT Thermostat that had a physical UI and temperature sensor built in.
This was achieved using Node and an i2c ADC on a Raspberry Pi W. This was done with lots of amazing example code from Tom Igoe, a few repos in particular:
https://github.com/tigoe/NodeExamples
https://github.com/tigoe/NodeSensorExamples
https://github.com/tigoe/MakingThingsTalk2
Our challenge was to have a device that would post the current temperature to a web server for a week. The twist being that we were going to be under attack by a red team trying to hack our devices.