Standalone Bluetooth
If you just want a Bluetooth device so you can pair your phone (or any other Bluetooth device), you can use the FC-114 alias HC-05 device:


Buy it in Amazon
Buy it in Ebay


It's a very simple device that you can connect using 5V power supply. It is designed to connect a microcontroller to it via serial communication. Microcontroller is not mandatory if your sole requirement is to pair your phone to it.

Depending on firmware variation, its pairing code is 1234 or 0000.

Here is a connection diagram:



There are a variety of manufacturers of HC-05 / FC-144. Depending on which one you buy, all devices in the same batch may share the same MAC address, which can be annoying depending on your application. These devices have so called AT-MODE which allows to configure them using a UART to transmit commands to the RxD/TxD connectors.

UART devices are available as embedded in a Microprocessor, or as a USB to UART adapter. As Ignacio mentions, command AT+BIND is able to set the Bluetooth address (See the communication protocol, page 10). I do not believe that the configured address is kept in Flash.