PaulS:
Threaten to take a sledgehammer to the device if it doesn't behave. I'm sure that the bluetooth device will shape right up.If that should fail to work, I suspect that Mr. Google has other advice that might be more useful.
You know, stupid sh*t like how to connect the device to the Arduino, how to set up a HardwareSerial instance or to create a SoftwareSerial instance so that the Arduino can talk to the bluetooth device, and get data from it.
Thanks for the effective answer.. I know that Mr.Google has some great answers, but I thought you come into this forum to get helps and tips on how to make better codes and ask questions about code.
I'm very sorry that my question is not as expected, as I'm working on a big project that I need to present in the next couple of weeks, and I just need some explanation on how to use the serial communication. I just don't understand how can I read data from a phone and guess it's baud rate. (Or for instance, I can set my baud rate on the Arduino to 9600 which is pretty fine and the phone will auto tune to that baud rate).