SOLUTION - Your project must have an Android package set in app.json React Native

SOLUTION - React Native Your project must have an Android package set in app.json

React native is a great choice to create an android and ios app by using the same codebase. You can create a simple hello world app and generate .apk and .ipa file but sometimes mostly first time we follow some tutorial and create a basic app and try to build app file or generate apk file by using the command  "expo build:android" or "expo build:ios", we get an error "Your project must have an Android package set in app.json", so here is the solution of this error:-

Solution 1
Open app.json file that should exist on your root directory
now check below code already exist or not, if not exist then add this code in your app.json file

"android": {
      "package": "com.shubham715.helloworld",
    },

For IOS

"ios": {
      "bundleIdentifier": "com.shubham715.helloworld",
      "supportsTablet": true,
    }

After adding above code, your file will be look similar to the below code:-

{
  "expo": {
    "name": "demo",
    "slug": "AwesomeProject",
    "privacy": "public",
    "sdkVersion": "36.0.0",
    "platforms": [
      "ios",
      "android",
      "web"
    ],
    "version": "1.0.0",
    "orientation": "portrait",
    "icon": "./assets/icon.png",
    "splash": {
      "image": "./assets/splash.png",
      "resizeMode": "contain",
      "backgroundColor": "#ffffff"
    },
    "updates": {
      "fallbackToCacheTimeout": 0
    },
    "assetBundlePatterns": [
      "**/*"
    ],
    "ios": {
      "bundleIdentifier": "com.shubham715.helloworld",
      "supportsTablet": true,
    },
    "android": {
      "package": "com.shubham715.helloworld",
    },
  }
}

and if its already exist then follow solution 2

Solution 2
Create a new fresh project by using expo command

expo init YourProjectTitle

Now move all your files in this newly created folder and then try again to build android  APK or IPA file, this time it will work.

Thanks

Related Links:
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