DS18B20 is a single-bus digital temperature sensor with features of ultra-small size, wide range of applicable voltage and measurable temperature and high resolution.

A Whadda Universal Temperature Sensor Mounting Kit, used for measuring indoor and outdoor temperatures, controlling the rise/fall of temperature in homes, equipment, control of temperatures in some processes, visualization of the temperature on your website, control of the temperature of your pool, etc.

Kit Thermostat with LED Indicator - Velleman.

Detecting temperature changes has never been easier. The MCP9700 is a small thermistor type temperature sensor. 

Temperature Sensor - Grove

Sparkfun Temperature and Humidity Sensor- SHT15

The kit does not require any soldering and is recommended for anyone with a drive to learn more about Blynk and its uses. So if you are looking for a new challenge or a way to get in on the IoT craze, check out the SparkFun IoT Starter Kit with Blynk Board!

SparkFun humidity sensor - HIH-4030

The Si7021 is a low-cost, easy-to-use, highly accurate, digital humidity and temperature sensor. 

The Earth Unit is a Sensor for measuring Humidity in Soil or Similar Materials. The Soil Moisture Sensor is quite simple to use. The two large stake-type sensors act as probes for the sensor, acting together as a variable resistance. The higher the moisture in the soil, the better the conductivity between the two, so that the sensor results in less resistance and higher GIS output.

You can read the moisture in the soil through ADC. Within this unit, there is an extra potentiometer to change the measurement range.

This package includes a Sensor of Level of Water and a Sensor of Humidity from Solo. If the plates have water covering the sensor components, an analog value will be available on the "SIG" connection. The Sensor of Level of Water can detect up to 4cm of water. This way, you can check if your aquarium, or your pet's water bowl, still has enough water. You can use the Sensor of Moisture of the Soil to check your plant's soil or growing environment, for example.

Sensor Temperatura PT-100