updateLocalStorage.js

var addToLocalStorageArray = function (name, value) {

	// Get the existing data
	var existing = localStorage.getItem(name);

	// If no existing data, create an array
	// Otherwise, convert the localStorage string to an array
	existing = existing ? existing.split(',') : [];

	// Add new data to localStorage Array
	existing.push(value);

	// Save back to localStorage
	localStorage.setItem(name, existing.toString());

};

var addToLocalStorageObject = function (name, key, value) {

	// Get the existing data
	var existing = localStorage.getItem(name);

	// If no existing data, create an array
	// Otherwise, convert the localStorage string to an array
	existing = existing ? JSON.parse(existing) : {};

	// Add new data to localStorage Array
	existing[key] = value;

	// Save back to localStorage
	localStorage.setItem(name, JSON.stringify(existing));

};

On line 24 you can change the last word "array" to an "object" since that's what this function is about, right.