Workflow — Cloud App Builder

Cloud Builder v1.0

What is Workflow Builder?

Workflow is a cloud build service that compiles your mobile app source code into a ready-to-install .apk file — directly on our server. No Android Studio, no local setup required. Just zip your project and upload.

This service is designed for AI-generated apps and developers who want a fast, server-side build without configuring a local environment.

How it works — 4 steps

Upload — Zip your entire project folder and upload it here. Max 500 MB.
Configure — Choose your project type, build mode (release/debug), and optionally upload your signing keystore.
Build — Our server runs the correct build tool (Flutter, Gradle, Expo) and signs your APK automatically.
Download — Your APK is ready. Download link expires in 30 minutes to keep the server clean.

Supported project types

Type	What gets run	Output
Flutter	flutter pub get → flutter build apk	.apk
React Native (Expo)	npm install → expo prebuild → gradlew assembleRelease	.apk
Native Android	./gradlew assembleRelease	.apk

Build times (estimate)

Project type	Cold build	Notes
Flutter	3–8 min	First build downloads Dart packages
React Native	5–15 min	npm install + Gradle can be slow
Native Android	2–6 min	Depends on project complexity

Flutter — Required project structure

Your ZIP must contain a complete Flutter project. The root of the ZIP should be the project root (where pubspec.yaml lives).

your-app.zip └── my_flutter_app/ (or files directly at root) ├── pubspec.yaml ← required ├── lib/ │ └── main.dart ← required ├── android/ ← optional, server generates if missing ├── ios/ └── assets/

You do not need to include the android/ or build/ folders — the server runs flutter build apk which generates everything.

pubspec.yaml must have

name: field set
flutter: section present
All dependencies listed under dependencies:
Assets listed if your app uses images/fonts

Common Flutter issues

Error	Fix
Plugin not found	Make sure plugin is in pubspec.yaml dependencies
minSdkVersion too low	Set minSdkVersion 21+ in android/app/build.gradle
Missing google-services.json	Include it in android/app/ inside your ZIP

React Native (Expo) — Required structure

Upload a complete Expo project. Do not include node_modules/ — the server runs npm install for you.

your-app.zip └── my-expo-app/ ├── package.json ← required ├── app.json / app.config.js ← required ├── App.tsx / App.js ← required ├── src/ ← your source files ├── assets/ ├── android/ ← optional └── ios/

Do not include node_modules/ in your ZIP — it will bloat the file and slow down the build. The server installs packages from package.json.

app.json must have

{ "expo": { "name": "My App", "slug": "my-app", "version": "1.0.0", "android": { "package": "com.yourname.myapp" } } }

The android.package must be a unique reverse-domain identifier like com.yourcompany.appname. This is required for the APK to install on a device.

Common React Native issues

Error	Fix
Package name missing	Add `android.package` to app.json
Missing dependency	Make sure all packages are in package.json
Native module not found	Some modules need prebuild config — check Expo docs

Native Android — Required structure

Upload a standard Android Gradle project. The root should contain gradlew and the app/ module.

your-app.zip └── MyAndroidApp/ ├── gradlew ← required (Gradle wrapper) ├── gradle/ │ └── wrapper/gradle-wrapper.properties ├── app/ │ ├── build.gradle │ └── src/main/ │ ├── AndroidManifest.xml │ └── java/ or kotlin/ ├── build.gradle └── settings.gradle

Do not include build/ or .gradle/ cache folders — they add hundreds of MB and will be regenerated during build.

build.gradle (app) requirements

android { compileSdk 35 defaultConfig { applicationId "com.yourname.app" minSdk 21 targetSdk 35 versionCode 1 versionName "1.0" } buildTypes { release { minifyEnabled false } } }

APK Signing — How it works

Every Android APK must be signed before it can be installed on a device. Workflow signs your APK automatically. You have two options:

Option 1 — Auto-detected (recommended): Include your .keystore or .jks file inside your ZIP. The server finds it automatically, reads the credentials from key.properties or your workflow YAML, and signs without any manual setup.

Option 2 — Upload separately: Use the "Override Signing Credentials" toggle in the Configure step to upload a .jks file and enter credentials manually. Useful when you don't want the keystore inside the ZIP.

Option 3 — Debug signing (fallback): If no keystore is found anywhere, the server signs with its own debug key. The APK installs on devices for testing but cannot be published to the Play Store.

Generate your own keystore

Run this once on your computer to create a production keystore you can reuse for every build:

keytool -genkey -v \ -keystore my-release-key.jks \ -alias my-key-alias \ -keyalg RSA -keysize 2048 \ -validity 10000 \ -storepass YOUR_STORE_PASSWORD \ -keypass YOUR_KEY_PASSWORD \ -dname "CN=Your Name, O=Your Company, C=US"

Keep your keystore safe! If you publish to the Play Store, you must use the same keystore for all future updates. Losing it means you cannot update your app on the store.

Privacy — your keystore is safe

Your keystore is uploaded over HTTPS (encrypted in transit)
It is stored in a temporary folder and deleted immediately after signing
It is never logged, stored permanently, or shared
The signed APK itself is deleted 30 minutes after the build

Upload

Configure

Build

Download

Upload Project

Drag & drop your project ZIP here

or click to browse · Max 500 MB

React Native Flutter Native Android

Build Configuration

Project Type

Build Type

Signing

Override Signing Credentials

Only needed if your ZIP has no keystore, or you want to supply credentials separately

Building your app...

Preparing environment

Build Successful!

Your APK is ready to download

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Type

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Build

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Size

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Duration

How to Use Workflow Builder

Upload Project

Build Configuration