Expo

Documentation

Workflows

The two approaches to building applications with Expo tools are called the "managed" and "bare" workflows.
  • With the managed workflow you only write JavaScript / TypeScript and Expo tools and services take care of the rest for you.
  • In the bare workflow you have full control over every aspect of the native project, and Expo tools can't help quite as much.
💡 If you've used React Native without any Expo tools then you have used the "bare workflow", but the name probably doesn't sound familiar. We call this "bare" somewhat in jest and because of the term "bare metal" which and it's easier to talk about something when it has a name. If you have direct access to the native code, it's a bare project. The "Already used React Native?" page might be useful for you to quickly understand where Expo fits in.

The managed workflow is kind of like "Rails" and "Create React App" for React Native.
Apps are built with the managed workflow using the expo-cli, the Expo client on your mobile device, and our various services: push notifications, the build service, and over-the-air (OTA) updates. Expo tries to manage as much of the complexity of building apps for you as we can, which is why we call it the managed workflow. A developer using the managed workflow doesn't use Xcode or Android Studio, they just write JavaScript code and manage configuration for things like the app icon and splash screen through app.json. The Expo SDK exposes an increasingly comprehensive set of APIs that give you the power to access device capabilities like the camera, biometric authentication, file system, haptics, and so on.
While you can do a lot with the managed workflow, you can't do everything with it, so what are your options when you encounter a limitation?
🤓 We will discuss the limitations more in depth soon, for now let's just look at what will happen if it turns out one applies to your application.

If you get to the point where you need to have full control over the native code in your app, you can "eject" (run expo eject in your project) and expo-cli will expose all of the underlying native projects and configuration. You'll then be using the bare workflow.

In the bare workflow the developer has complete control, along with the complexity that comes with that. You can use most APIs in the Expo SDK, but the build service, notifications, over-the-air updates, and easy configuration with app.json are not yet supported. You can refer to tutorials and guides that are oriented towards native iOS and Android apps and React Native for alternatives.

  • 🚫🔒Expo never locks you in, you can "eject" at any time and your project will just be a typical native project with the React Native and Expo SDK packages that your app is using installed and configured.
  • 🆕If you are new to mobile development or new to development in general we recommend that you use the managed workflow. There is a huge amount of complexity that comes along with the native development toolchain and the managed workflow allows you to deal with that complexity only when absolutely necessary.
  • 🧠 If you are more experienced it also doesn't hurt to start every new project with the managed workflow and only "eject" if you need to.
In summary, use the bare workflow when you need it due to limitations, otherwise use the managed workflow, and you most likely want to start with the managed workflow.