Classic bluetooth connection on Arduino

//  use the following sample to connect to the mobile Serial bluetooth terminal app by Kai Morich to test // modules are working or not

#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 4); // RX, TX configured on Arduino to TX, RX of bluetooth module

void setup() {

  // Open serial communications and wait for port to open:

  Serial.begin(9600);  // so far, it seems 9600 is the working baudrate

  while (!Serial) {

    ; // wait for serial port to connect. Needed for native USB port only

  }

  Serial.println("Goodnight moon!");

  // set the data rate for the SoftwareSerial port

  mySerial.begin(9600);

  mySerial.println("Hello, world?");

}

void loop() { // run over and over

  if (mySerial.available()) {

    Serial.write(mySerial.read());

  }

  if (Serial.available()) {

    mySerial.write(Serial.read());

  }

}