[Slave HC-06] Data sending , android app to arduino via bluetooth

Hi, i’m a student who have to do a project and my part consist of sending data from android app (MIT App inventor 2) to arduino and i make a program which don’t work and i don’t know why

" I tried to look in the forum but i found anything "

So here is my code :

#include <SoftwareSerial.h>

SoftwareSerial HC06(10,11);
int data;

void setup()
{
Serial.begin(9600);
HC06.begin(9600);
}

void loop()
{
while(HC06.available())
{

delay(100);
char c = HC06.read();
data += c;

Serial.println(data);
}
}

You might find the following background notes useful.

http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2BT.pdf
http://homepages.ihug.com.au/~npyner/Arduino/BT_2_WAY.ino