J. Bremnant writes about a led clock with bluetooth capabilities that can be controlled from an Android phone or a pc with a bluetooth dongle.
"I came across this neat bluetooth module called HC-06. It can be found as cheap as $6 on ebay, and gives you convenient UART access to bluetooth wireless capabilities.
My 3yr old has this home-made LED clock in his room. I thought it was time for an upgrade since the clock was very minimalistic. Its only function was to keep track of time and display it on the LED panel. And considering it was my first 1Ccompleted 1D project with avr (atmega168), I thought I could make it better this time around.
I wanted to make use of bluetooth capability somehow, and thought it would be neat to send a text message to the display. In addition, I decided change up a few things:
receive bluetooth text message up to 64 chars and scroll it across the panel
set the time via bluetooth
consolidate 2 push buttons into 1 for manual time adjustment
make some noise with the piezo I put in there
The upgrade seems to have worked out nicely. I can send messages to it from my Android phone or from a Linux PC with bluetooth dongle attached. I used iteadstudio 19s bluetooth assistant app to send text to the display."