In this chapter, we will take a look at Bluetooth technology and how to make your own activity and gesture-monitoring device. Bluetooth is a standard for wireless communication between devices that was developed by the Swedish telecom company Ericsson in the 90s. The Nordic Viking king, Harald Blåtand, who united the Norwegians and the Danish, was known for his communication skills and as a great speaker inspired the name Bluetooth. The word Bluetooth is a direct translation of his last name, which seemed fitting.

The actual technology was off to a slow start and struggled for its existence for the first year, but now it's safe to say that it has become a success and the market has exploded with Bluetooth connected devices. Today, it seems that everything is connected with Bluetooth. Cars, controllers, headphones, keyboards, and even lamps connect to other devices over Bluetooth. In 2010, Sony started the development of a Bluetooth version called smart Bluetooth, a...