Create a local function called eggTimer() and use timer.performWithDelay to drop an egg every 1 second (1000 milliseconds) repeatedly. Use eggDrop() to activate the drop:

    local eggTimer = function()
      startDrop = timer.performWithDelay( 1000, eggDrop, 0 )
    end

Within the first if statement in the onEggCollision() function, cancel the timer using the timerID and startDrop variables. Add the if gameLives < 1 statement then to stop the eggs from falling:

      if gameLives < 1 then
        timer.cancel( startDrop )
        print("timer cancelled")
      end