Is it possible to initially create a Client Side Only app then later on implement the Server Side?

I will try to clarify what I mean. Lets say you have an idea for an app but you don't have the money and means to initially implement the idea in its entirety(communicating with server side/back end). But the core idea can still be implemented as a purely front end client side app while allowing the users to store information on their devices.

Is there a way to initially take a 'minimum viable product' approach with client side only core idea of the app then later on add in the back end stuff and grab the data stored from the user's devices and store it on a database to be implemented into the full realization of the app?

I hope what I am saying makes sense. As you can see I am not yet knowledgeable on the proper term usage on this subject. If not please ask if anyone is confused about anything and I will try to give a better explanation.