Store and retrieve data from device

Id like to get some help with storing and retrieving data!

Have already checked Studio | Storing Persistent Data

But that didnt help me so much since im not programmer. It is bit hard for beginner to understand what i really need to write, when to use what symbols etc. I tried and tried but didnt found any solution

My problem is how to store and retrieve high scores beetween scans (Im using webAR)

My code looks like this, tutorials did help me very much to write that! Thank you everyone for that.

const Score = symbol.nodes.Score;
const Scoreboard = symbol.nodes.Scoreboard;

let score = 0;
let scoreIncrement = 1;
let minusScore = 1;

// This function adds score
function add(){
    score += scoreIncrement;

// This function is minus score
function minus(){
    score -= minusScore;

//this pointerdown event call add-functiion
symbol.nodes.Pointer.on("pointerdown", (e) => {

//this pointerdown event call minus-function
symbol.nodes.Minuspointer.on("pointerdown", (e) => {

symbol.nodes.SaveyourScore.on("pointerdown", (e) => {"Points", score);

symbol.nodes.SaveyourScore.on("pointerdown", (e) => {
    Z.device.retrieve("Points", function(data){
    if (data == undefined){
    //nothing happes
    } else {
    //call your score



Some kind of “store and retrieve data for dummies 101”- code would be so helpful!