This version of Android Bluetooth chat is by using original google source code example of Android Bluetooth chat. This is for easy understanding and quick integration of Bluetooth capabilities in the application by copying all the the java files in app/src/main/java/group/project/btech/bluchat_extend. There is MainActivity file in which there is some code which is very simple and self explanatory. Copy it and paste it in your project and merge the code in OnCreate method and make your own of the same and ceate interesting applications. Peace :)