The HC-05, a Bluetooth to serial bridge, can be found for around $5 on the internet and therefore may be the cheapest way to add Bluetooth connectivity to your project. However, its default setting… ...

Looking for practical Arduino projects? This guide shows how to control a relay from your smartphone using an Arduino Uno — ...

The Arduino, Bluetooth module (check your specs, some HC-05, and HC-06 may come on a breakout board expecting 5V), and USB Host shield all run off of 3.3V, but devices you want to plug into the ...

This is a simple project. It uses an Android device to switch an LED driven by the Arduino. Connectivity is provided by the Bluetooth module inserted in the breadboard. But one look at the UI on th… ...

DastardlyLabs uses a USB host shield, a Bluetooth module, an Arduino Pro Mini, and a bunch of other random parts to create this little device.