Here is my android controlled arduino project. A simple app sends data through SPP over bluetooth and switches an LED on and off.
The circuit is just a bluetooth module, arduino UNO, LED, resistor and some wires.
The LED can be switched on using buttons as well as voice activation (anything that contains the word 'on','off' or 'blink' - so saying 'turn the LED on' works as well as just uttering 'on').
I created the app using MIT app inventor and this project was created pretty much only to show how easy it is to write custom apps using the tool and interface with microcotrollers in this manner. One could use MIT app inventor to add more more features, such as using accelerometer or GPS data to control the LED, switching the state using text messages, web communication, not only send but also receive data, etc.
...well the point is - MIT app inventor is pretty cool and you should check it out
VIDEO OF IT ->
http://youtu.be/41MRGjdVIMQ



Here is the app for download ->
http://speedy.sh/63Q9N/bluetoothforarduino-app-2.apkand here is the source, you can upload it to MIT's app inventor and modify as much as you want to ->
http://speedy.sh/mDyAk/bluetoothforarduino-app-1.zipHere is the arduino code
const int ledPin = 7; // the pin that the LED is attached to
byte serialA;
void setup()
{
// initialize the serial communication:
Serial.begin(19200);
// initialize the ledPin as an output:
pinMode(ledPin, OUTPUT);
}
void loop() {
switch (serialA) {
case 1:
digitalWrite(ledPin, HIGH);
break;
case 2:
digitalWrite(ledPin, LOW);
break;
case 3:digitalWrite(ledPin, HIGH);
delay(100);
digitalWrite(ledPin, LOW);
delay(100);
}
}
void serialEvent(){
serialA = Serial.read();
}