Reset PlayerPrefs on Build?

@Designosaurus

These were a way to delete all playerPref

 PlayerPrefs.DeleteAll();

And you can try redirect all your setting. by check if you are in editor. Like this

 if (Application.isEditor) //Does application is running in editor?
 {
     PlayerPref.SetInt("Editor-someSetting", 0);
 }
 else //If not in editor
 {
     PlayerPref.SetInt("someSetting", 0);
 }

But.... what if I prefer you to replace all your current PlayerPref with JSON?

Anyway. If you want it or not. I'll give you a look anyway.

Here is setting script (Don't attach this to GameObject)

 using System.IO;
 using UnityEngine;
 
 public class UserSettings
 {
     public string setting1;
     public int setting2;
     public float setting3;
 
     public UserSettings() //Initialize new Setting
     {
         setting1 = "New setting";
         setting2 = 0;
         setting3 = 0f;
     }
 
     //Save setting to json file
     public static void Save(UserSettings info, string filename)
     {
         //Extent filename to actual path
         if (!filename.StartsWith("/"))
         {
             filename.Insert(0, "/");
         }
         filename = filename.Insert(0, Application.persistentDataPath);
         //Check if file exist or not. If it exist. Delte it. Because we about to save a new one.
         if (File.Exists(filename))
         {
             File.Delete(filename);
         }
         //Turn all user setting to Json. (as a string json)
         string todisk = JsonUtility.ToJson(info);
         //Write json string to disk
         using (FileStream fs = new FileStream(filename, FileMode.CreateNew, FileAccess.Write))
         {
             StreamWriter wt = new StreamWriter(fs);
             wt.Write(todisk);
             wt.Close();
         }
     }
     
     //Load setting from json file
     public static UserSettings Load(string filename)
     {
         //Extent filename to actual file
         if (!filename.StartsWith("/"))
         {
             filename.Insert(0, "/");
         }
         filename = filename.Insert(0, Application.persistentDataPath);
         //Check if that setting file was exist or not
         if (File.Exists(filename))//If exist
         {
             //Read that file and return it
             using (FileStream fs = new FileStream(filename, FileMode.Open, FileAccess.Read))
             {
                 StreamReader rd = new StreamReader(fs);
                 string fromdisk = rd.ReadToEnd();
                 return JsonUtility.FromJson<UserSettings>(fromdisk);
             }
         }
         else //If not exist
         {
             //Return new setting
             return new UserSettings();
         }
     }
 }

And here is how to use it. Attatch this script in scene

 using UnityEngine;
 
 public class MainGameClass : MonoBehaviour
 {
     //This is a setting collection variable;
     public UserSettings currentSetting;
 
     //Load setting when start game
     void Awake()
     {
         if (Application.isEditor)
         {
             currentSetting = UserSettings.Load("Editor.json");
         }
         else
         {
             currentSetting = UserSettings.Load("user1.json");
         }
     }
 
     //Use the setting
     void UseSetting()
     {
         currentSetting.setting1 = "New setting apply...";
         currentSetting.setting2 = 69;
         currentSetting.setting3 = 6.9f;
     }
 
     //Reset setting
     void ResetSetting()
     {
         currentSetting = new UserSettings();
         UserSettings.Save(currentSetting,"user1.json");
     }
 
     //Save your setting
     void SaveGameSetting()
     {
         UserSettings.Save(currentSetting, "user1.json");
     }
 }

 bool firstPlay;
 
 void Awake ()
 {
 if (Application.isEditor == false) {
      if (PlayerPrefs.GetInt ("FirstPlay", 1) == 1) {
           firstPlay = true;
           PlayerPrefs.SetInt ("FirstPlay", 0);
           PlayerPrefs.Save ();
      } else
           firstPlay = false;
 }