Chapter 2: Don’t Start Coding Just Yet

Once you have a good understanding of your users and what they want, it is tempting to start coding. You probably already have an idea in your head how the app will look and function. But don’t jump into coding just yet! Code is rigid and difficult to change. It is better to use more flexible ways to think about the design first.

The app-building process is a continuum from low-fidelity ideas on paper to high-fidelity designs and working prototypes toward the final product. This chapter introduces some tools and ideas that will help you on the way.


Draw your design ideas on paper first. Getting ideas from your head to paper will make them concrete and much easier to discuss with the rest of the team. This phase of app building is called prototyping. Prototyping is an essential part of the design process. It provides a way to test ideas without having to implement them, therefore giving the team greater creative freedom.

The purpose of a prototype is to simulate the functionality of the app you are building. The simulated functionality will let you experiment and expose problems that you and your team might not have thought about. A prototype can be a low-fidelity paper drawing that doesn’t have any real functionality or a high-fidelity functional prototype that can actually be used and experienced—or anything in between.

Tip: The best place to start prototyping is on paper. Paper is virtually free and paper prototypes can be ...

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