Win mobile app and bluetooth

Hei, I am planing to make an app for Windows Mobile using C#. The app is going to communicate with the Arduino Main Board, setting pins High or Low. So I need some sort of bluetooth receiver.

http://cgi.ebay.com/Arduino-Serial-Port-Bluetooth-Baseboard-Master-/280509902153?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item414fb16d49

Is that something that I can use? If not, what do i need?

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