Not sure if you have this issue still, or if anyone else does that might find this. but the tutorial says to declare the method:(in HelloWorldScene.h)
As @buntynara said, in version 3, onTouchesEnded is the proper method to use.
In order for this function to be called, the method must be defined as follows:
I am unsure if this is the best/correct way for this to be declared, all I know is that when I went through the Cocos tutorials, this worked for me.