yandex-maps service for save places I made script which create marker on the map after mouse left button click. And after mouse right button click marker removed.

All markers coordinates storage in browser localStorage.

I use yandex-maps technoogy.

JSFIDDLE

code:

ymaps.ready(init);

var myMap,
    collectionMarkers,
    myPlacemark;

function init(){     
    myMap = new ymaps.Map("map", {
        center: [55.76, 37.64],
        zoom: 7
    });

    collectionMarkers = new ymaps.GeoObjectCollection({}, {
        preset: "islands#redIcon"
    }); 

    myMap.geoObjects.add(collectionMarkers);

    renderSavedPoints();

    myMap.events.add('click', function (e) {
        var coords = e.get('coords');
        //console.log('lat:', coords[0], 'lng:', coords[1]);

        var placemark = new ymaps.Placemark([coords[0], coords[1]]);    
        collectionMarkers.add(placemark);  

        addToStoragePoint({
            lat: coords[0],
            lng: coords[1]
        });       
    });

    collectionMarkers.events.add('contextmenu', function(e) {
        var coords = e.get('target').geometry.getCoordinates();

        var pointLat = coords[0],
            pointLng = coords[1];

        //console.log('right click', pointLat, pointLng);   

        var points = getPoints(),
            newPoints = [];

        newPoints = points.filter((point) =&gt; point.lat != pointLat &amp;&amp; point.lng != pointLng);    

        localStorage.points = JSON.stringify(newPoints);    
        renderSavedPoints();              
    });       
};

function getPoints() {
    return localStorage.points ? JSON.parse(localStorage.points) : [];
};

function addToStoragePoint(pointObj) {
    console.log('addToStoragePoint start');
    var points = getPoints();
    points.push(pointObj);
    localStorage.points = JSON.stringify(points);
};

function renderSavedPoints() {
    var points = getPoints();

    collectionMarkers.removeAll();

    points.forEach((point) =&gt; {        
        var placemark = new ymaps.Placemark([point.lat, point.lng]);         
        collectionMarkers.add(placemark);
    });
};
You should be using function such as:

localStorage.setItem('points', JSON.stringify(points));
localStorage.getItem('points');


If you can use es6:

// instead of 
var coords = e.get('target').geometry.getCoordinates();

var pointLat = coords[0],
    pointLng = coords[1];

// Could write  
const [pointLat, pointLng] = e.get('target').geometry.getCoordinates();

// Why save points as variable if it's only used once
var points = getPoints(),
    newPoints = [];

newPoints = points.filter((point) =&gt; point.lat != pointLat &amp;&amp; point.lng != pointLng);    
// Could just do
var newPoints = getPoints().filter(point =&gt; point.lat != pointLat &amp;&amp; point.lng != pointLng);