The Bluetooth module wants 3.3v logic levels so that is ... The software end of things consists of an Arduino sketch and an Android app. Check out all the controls on that screen.

Once paired, these modules relay serial information from your smart device to the dev board and vice versa. Just reverse the receive (Rx) and transmit (Tx) lines between your Arduino and Bluetooth ...

Here’s a nifty programmer for a cheap Bluetooth module. So just how cheap is this part? Does $6.60 sound like an extreme deal? The information on this hack is spread throughout a series of posts.