High Score Save iOS

Hi, so I am trying to get the high score to work on my iOS device. I currently have the app on my phone using TestFlight but I need help with the high score as it is just blank. I am not the best scripter and I am using JavaScript. Below is my script..

Please help me get this to work on my APPLE DEVICE.

ScoreLoad.js:

 import System.IO;
 
 static var CompareScore : int;
 var fileName = "highscore.data";
 var ScoreLoad : String;
 var HighScoreDisplay : GameObject;
 var line : String;
 
 function Start () {
 //sr is short for streamreader
     //var sr : StreamReader = new StreamReader(fileName);
     //line = sr.ReadLine();
     //    while (line != null) {
     //        ScoreLoad = line;
     //        line = sr.ReadLine();
     //    }
     //sr.Close();
 
     ScoreLoad = PlayerPrefs.GetString("HighScore");
 
     HighScoreDisplay.GetComponent.<Text>().text = "Best: " + ScoreLoad;
 
     CompareScore = int.Parse(ScoreLoad);
 }

ScoreSave.js:

 import System.IO;
 
 var fileName = "highscore.data";
 var ScoreAmount : int;
 var HighScore : int;
 
 function Start () {
     HighScore = ScoreLoad.CompareScore;
     ScoreAmount = Score.TheScore;
     if (ScoreAmount >= HighScore) {
     //var OurFile = File.CreateText(fileName);
     //    OurFile.WriteLine (ScoreAmount);
     //OurFile.Close();
     PlayerPrefs.SetInt("HighScore", ScoreAmount);
     }
 }

Score.js:

 import UnityEngine.UI;
 
 static var TheScore : int;
 var ScoreDisplay : GameObject;
 var EndScoreDisplay : GameObject;
 
 function Start () {
     //After 0 seconds "AddScore" starts. From then on it starts every 0.1 seconds.
     TheScore = 0;
     InvokeRepeating("AddScore", 0, 0.1);
 
 }
 
 function AddScore () {
     TheScore += 0;
     ScoreDisplay.GetComponent.<Text>().text = "Score: " + TheScore;
     EndScoreDisplay.GetComponent.<Text>().text = "Score: " + TheScore;
 }