USB Bluetooth for serial communication

[germ]

Hey!
I was thinking of adding a bluetooth device to a spark, to make it do things with my phone.
As far as I understand, bluetooth-modules with a serial communication/connection is they way people usually do this.
Now I have a standard USB-bluetooth adapter lying around, and I was wondering if there is any way for the sparky to talk to that thing.
I've seen serial to USB converters, but is it possible to reverse it? Or even connect to it as is?
Thanks!

[gogol]

I don't know, if that is worth the price.
Search for HC-05 at ebay, amazon, aliexpress, ..  you get serial Bluetooth-devices for around $5. 

And that device is able to connect through USB, serial, SPI !  Se for example: https://mbed.org/users/edodm85/notebook/HC-05-bluetooth/

Maybe you are lucky, and inside your device is a similar chip, where you need only to connect RX/TX.