Below is a dynamic chart of an IoT temperature sensor that I made to monitor the indoors or outdoors temperature at home. I am using a free Android app called “IoT ThingSpeak Monitor” by Wilice. The app allows you to setup a widget to display the temperature and to set lower and upper limit temperature alarm notification triggers. The system uses the following technologies:
esp8266-01 – this is a low cost WiFi SoC with a couple of General Purpose I/O.
Dallas DS18B20 – this is a low cost one wire temperature sensor.
Programmed with Arduino IDE – this is a free IDE used to develop the software.
Thingspeak.com – used to store and chart data with a free account.
IoT ThingSpeak Monitor Widget – used to monitor and alert free from Goolge Play