You can read what is received by the HC-06 module, with the Arduino, as a normal serial entry. An example of code (to read and write) can be this:
#include <SoftwareSerial.h>
// Define os pinos para comunicação de série (RX, TX)
// Pinos 6 e 7 neste caso
SoftwareSerial MinhaSerial(6,7);
String command = "";
void setup()
{
// Inicia a comunicação de série com o PC
Serial.begin(115200);
Serial.println("Digite os comandos AT :");
// Inicia a comunicação de série com o módulo BT (portas 6 e 7)
MinhaSerial.begin(9600);
}
void loop()
{
// Se o módulo BT tiver bytes para ler
if (MinhaSerial.available())
{
// Enquanto o módulo BT tiver bytes para ler
while(MinhaSerial.available())
{
// Acrescentar os bytes lidos à variável "comando"
comando += (char)MinhaSerial.read();
}
// Deixando o módulo de ter bytes para ler
// Imprimir a variável "comando" para a interface de série ligada ao PC
Serial.println(comando);
// Fazer reset à variável "comando"
comando = "";
}
// Se a interface do PC tiver bytes para ler
if (Serial.available())
{
// Esperar 10ms
delay(10);
// Escrever para o módulo BT o que é recebido do PC
MinhaSerial.write(Serial.read());
}
}
Arduino must have 2 interfaces in series, one to connect to the PC and the other to the Bluetooth module. This example was taken from here.
In order to communicate with an android phone I advise you first to use an application that works as a finish Bluetooth, such as Bluetooth Terminal.
After you can verify that there is indeed communication between Arduino and android is that you should (if you want to) create an application of your, for example using Cordova/Phonegap/Phonegap Build and the plugin Bluetoothserial to read BT data in your app.
This way, if you know web programming (JS, HTML and CSS) you do not need to program natively on android, which may be good for those who are starting.