Starting the process

What can be built?

Emergent's mobile build system supports two types of mobile applications:

Native Android apps - compiled APKs that install on Android devices and publish to Google Play Console.
Native iOS apps - built and uploaded directly to your TestFlight for testing and App Store submission (no IPA file is handed to you).

Platform support note

Apple Watch and iPad apps can be coded (Swift/SwiftUI) within Emergent but cannot yet be published to the App Store through the platform. Support for these platforms is coming soon.

All mobile apps are built using React Native and the Expo framework, which share a single codebase for both iOS and Android.

Requirements

Before you start building, make sure you have:

An Emergent account

The Expo Go app (for testing)

Download Expo Go on your phone - it's free on both the App Store (iOS) and Google Play (Android). You'll use it to scan a QR code and preview your app live without publishing.

Developer accounts (for publishing)

To ship to production, you need:

Apple Developer Program account ($99/year) for iOS.
Google Play Console account (one-time $25 fee) for Android.

Warning

Apple account approval takes 24-48 hours. Create your account early in the process to avoid delays when you're ready to publish.

For more on the publishing step, see Publishing to the stores.

What is Expo?

Expo is the open-source framework and toolchain that powers every mobile app you build in Emergent. It sits on top of React Native and provides:

A managed build service (no Xcode or Android Studio required on your machine).
A comprehensive library of native modules (camera, location, notifications, etc.).

Expo Go is a free companion app for iOS and Android. During development, you scan a QR code from the Emergent workspace and your app runs live on your device - no need to compile an APK, no App Store submission, no waiting. Code changes appear instantly.

Tip

Think of Expo Go as a live sandbox: it's perfect for prototyping, iteration, and demos. When you're ready to ship, Emergent builds a standalone binary you submit to the stores.

Development workflow

Building a mobile app in Emergent follows a tight feedback loop between you and the agent:

Open a new Mobile App job and describe your app

Navigate to the Build › Mobile Apps section of your workspace. Start a new conversation with the Mobile Agent and describe what you want to build - features, screens, data, design preferences, integrations.

Answer clarifying questions

The agent will ask follow-up questions about authentication, navigation style, API endpoints, branding, and any ambiguities in your request. Answer these in the chat to refine the spec.

Preview live on your phone via Expo Go

Once the agent generates the app, it displays a QR code in the workspace. Open Expo Go on your phone, tap Scan QR code, and point your camera at the screen. Your app launches immediately.

Info

The preview is cloud-hosted via Expo tunnel, the only requirement is that your phone is online. If you see a connection error, check your network connection.

Iterate and debug with the agent

Test the app on your device. If something is broken or missing, describe the issue in the chat. The agent will update the code, and the preview reloads automatically. Repeat until you're satisfied.

Move to publishing when ready

When the app is stable and feature-complete, press Publish to publish the app first. Once published, you'll see Publish to App Store and Publish to Play Store options - tapping one generates the production build. See Publishing to the stores for the full flow. Native builds require a paid Emergent plan.

Converting an existing web app?

If you've already built a web app in Emergent and want a mobile version, see Web to Mobile conversion for guidance on adapting layouts, navigation, and state.

For a step-by-step walkthrough of your first build, see Your first build (walkthrough). For an overview of how Emergent turns chat into published apps, read The chat-to-published app flow.