When building apps, it's often better to download a subset of a list. Firebase has two types of databases that are as follows. shows and filter the products by category, Shows the specification of each product (their price, description, etc), Allows to comment for each product (only authenticated users), Customized shopping cart for add and remove products anytime, real-time calculation about the total cost of the current products in the shopping cart, correct structure of the database to avoid unnescessary data, user experience interacting with the interface, Admin mode, publish and customize the products, nested comments for reply comments made by other users, implementation of Js frameworks that allow reduce the amount of code (React, Angular, Polymer), add different authentication providers (Google, Facebook, GitHub), add Captcha when the user inserts an invalid password multiple times, Create a new project with the name of your preference, in the 'Web configuration' Panel copy the code of the second '