There are several options for what you are describing. It is possible to store all data in non-persistent objects, which live on the clientside and are never written to the database. The downside is that they get wiped when the session ends, so you will have to ask yourself for how long you want the data to be stored on the client. PWA's and Native apps have long-lived sessions and a local database where data can be stored independent from the server. A PWA (progressive web app) has the advantage that it's still a web app, but not all browsers are compatible (yet).