Unity FPS Limit

    public float goalFPS = 30;
    private float millisecondsToWait;

    // Update is called once per frame
    void Update () {

        float overflow = 1.0f/goalFPS - Time.deltaTime;

        if (overflow > 0.0f)
            millisecondsToWait ++;
        else
            millisecondsToWait --;

        Thread.Sleep((int)Mathf.Clamp(millisecondsToWait, 0.0f, 1.0f/goalFPS * 1000.0f)); // clamp for sanity

        if (SystemInfo.graphicsDeviceID == 0)
            return;

    }