Knockout persistence to localStorage. This is a very simple way to persist the value of a knockout observable to local storage. Every time you set the value of the observable it is also stored in the localStorage. You can indeed use this mechanism with any storage system.

ko-persist.js

ko.extenders.persist = function (target, option) {
    target.subscribe(function (newValue) {
        window.localStorage.setItem(option, newValue);
    });
    return target;
};

//and use it like this:

var item = ko.observable().extend({persist:"storedItem"});

//or if you want to also initialize the observable with the stored value:

var item = ko.observable(window.localStorage.getItem("storedItem")).extend({persist:"storedItem"});