Using an HC05 bluetooth module i connected my arduino board to my phone through an android app called "Arduino Bluetooth Control".

Components Used:-HC05 Bluetooth module,Arduino Board,Led light and Jumper wires

Working:-Using a serial Communication at a baud rate of 9600 we connect our HC05 to the Board using the app and send a value of 1 in order to light the led.Connect the longer pin of the led to the pin 2 of arduino and the other end to pin 3.The HC05 can be connected according to the following diagram.

Code:-

void setup()

{

Serial.begin(9600);

pinMode(2,OUTPUT);

pinMode(3,OUTPUT);

}

void loop()

{

while(Serial.available()!=null)

{

if(Serial.read()=='1')

{digitalWrite(2,HIGH);digitalWrite(3,LOW);}

else if(Serial.read()=='2')

{digitalWrite(2,LOW);digitalWrite(3,LOW);}

}

}