Setting up the folder structure

Let's initialize a React Native project using React Native's CLI. The project will be named guitarTuner and will be exclusively available for iOS:

react-native init --version="0.45.1" guitarTuner

As this is a single-screen app, we won't need a state management library such as Redux or MobX, so, we will use a simple folder structure:

We have three images to support our custom interface:

• indicator.jpg: The red bar indicating how tuned a string is
• tuner.jpg: The background in which the indicator will move
• string.jpg: A representation of a guitar string

Our src/ folder contains two subfolders:

• components/: This stores the <Strings/> component and the <Tuner/> component
• utils/: This holds a list of functions and constants which will be used in several parts of our app

Finally, the entry point of our...