Counter 1 times add

Unity Engine
1

hey how can I up counting a counter only once no matter if I hold down
i havea plane that has a function as button. If i click or touch in the screen it gets a raycast to the plane. i want that if i clicked on that plane, the counter only ONE time get one add. but now if i click on the plane its add how long i click.

			if(hit.collider.name.Equals("+")){
				if(Input.GetMouseButton(0)){
					lastHitObj.GetComponent<Turret_MG_ORIGINAL>().dmgLvl += 1;
				}
			}
2

Use Input.GetMouseButtonDown(0) instead of Input.GetMouseButton(0)

3

yeah but then it doesnt work no more on my Mobilephone … its a android game

work it with

if (Input.touchCount > 0  Input.GetTouch (0).phase == TouchPhase.Began) {

or another TouchPhase ?