public GUIText scoreText;
public GUIText timerText;
private int score;
public float seconds = 0f;
public float minutes = 0f;
public float moreSeconds = 0f;


void Start()
{
    score = 0;
    UpdateScore ();
    moreSeconds = Time.realtimeSinceStartup;
}

void Update()
{
    seconds = Time.realtimeSinceStartup - moreSeconds;
    if (seconds > 60)
    {
        seconds = 0;
        moreSeconds = Time.realtimeSinceStartup;
        minutes = minutes + 1;
    }

    if (seconds < 10)
    {
        timerText.text = "Time: " + (int)minutes + " : 0" + (int)seconds;
    }
    else
    {
        timerText.text = "Time: " + (int)minutes + " : " + (int)seconds;
    }
}

public void AddScore(int scoreInc)
{
    score += scoreInc;
    UpdateScore ();
}

void UpdateScore()
{
    scoreText.text = "" + score;
}