Tonight, I start working on a third project I have in my hack list for the moment, this one is based on bluetooth and I order some arduino stuff to make it live. The arduino itself is a leonardo and the bluetooth is a hc-05 attached to a larger shield to be connected with arduino board directly.
This article details how to use HC-05 to transfer data between arduino & mobile device based on Bluetooth. It includes HC05 source code for pairing and communicating.
Click on link to get more