Not sure why I started with WP8 app. I guess this is because I like C# or have WP8 or both. Anyway, my first version looked nice. Once I installed it on my phone and let my son to play with it, he immediately discovered several UI flaws (you can see some on the included Video), so I had to make changes to make UI run smoothly.
I'm still in the process of cleaning and fixing the code. I'll be posting the source code on GitHub once done. In case if you don't have Windows Phone Developers account, you can get the app from the Windows Store: http://www.windowsphone.com/en-us/store/app/bt-control/fe4d8895-3623-4633-8d42-edbb17857368