Have you ever stuck an Arduino in a hard to get place such as under the house and then realised that you want to upload a firmware revision? This can be a very frustrating situation, however, with the simple addition of a Bluetooth module it is possible to avoid this problem. Amazingly it is possible to program an Arduino over Bluetooth. For added flexibility there is even an Android app, “Bluino Loader” which allows you to upload a sketch to an Arduino from your smartphone. For step by step details of how this is possible, checkout the following link.
If you are looking for an easy way to add Bluetooth connectivity to your Arduino why not check out the Freetronics Bluetooth Shield?
Our Bluetooth Shield plugs right in to your Arduino and lets you send and receive data and commands from your sketches. You don't even need to do anything fancy in your sketches, because the Bluetooth link acts as a serial port: you just pair it with your computer, then you can simply use "Serial.read()" and "Serial.write()" as normal! The Bluetooth Shield can operate as a Bluetooth master or slave and is packed full of useful features. To find out more check out the Freetronics Bluetooth Shield product page.