There are many so-called 'Arduino compatible' platforms on the market. The ESP8266 – in the form of the WeMos D1 Mini Pro – is one that really stands out. This device includes WiFi Internet access and the option of a flash file system using up to 16 MB of external flash memory. Furthermore, there are ample in/output pins (though only one analogue input), PWM, I²C, and one-wire. Needless to say, you are easily able to construct many small IoT devices!

This book contains the following builds:

• A colourful smart home accessory
• refrigerator controller
• 230 V power monitor
• door lock monitor
• and some further spin-off devices.

All builds are documented together with relevant background information for further study. For your convenience, there is a small PCB for most of the designs; you can also use a perf board. You don’t need to be an expert but the minimum recommended essentials include basic experience with a PC, software, and hardware, including the ability to surf the Internet and assemble PCBs.

And of course: A handle was kept on development costs. All custom software for the IoT devices and PCB layouts are available for free download from at Elektor.com.