How to use GUI.Button in-game?

I have a game for Android that I want to have two GUI.Buttons on each top corner, one for “Flashlight” and one for “Batteries”.

I have currently learned how to use Application.LoadLevel with the GUI.Button script, but I don’t know how to accomplish my goal in adding these two functions in the game.

If anyone can help me out or point me to a tutorial about this, I would be very grateful.

var flashlightOn : boolean = false;
function OnGUI ()
{

if (GUI.Button (Rect (10,10,150,100), "flashlight")&& flashlightOn == false) 
        {
	flashlightOn = true;
	}
        else
        {
        flashlightOn = false;
        }
}

function Update ()
{
if(flashlightOn == true)
   {
    do something
    }
}

this will help you out if you have anymore questions. Do you need help with the flashlight part also?