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Youngho Chaa cha cha

Everything about Expo

expo, react native3 min read


  • EAS Get started
  • EAS Update tutorial
  • Github Actions

EAS Build

Install the latest EAS CLI

npm install -g eas-cli

Log in to Expo account

eas login

If you haven’t configured the project, do it

eas build:configure

Run a build

eas build --platform ios

Once the build is complete, submit the build to the App Store

eas submit --platform ios

EAS Update

EAS Update makes fixing small bugs and pushing quick fixes a snap in between app store submissions. It accomplishes this by allowing an end-user's app to swap out the non-native parts of their app (for example, JS, styling, and image changes) with a new update that contains bug fixes and other updates.

Install expo-updates

npx expo install expo-updates

Add the plugin to app.json

"plugins": [
"username": "deepeyes"

Import expo-updates in App.tsx and check the update

import * as Updates from 'expo-updates'
const onFetchUpdate = async () => {
const { isAvailable } = await Updates.checkForUpdateAsync()
if (isAvailable) {
await Updates.fetchUpdateAsync()
await Updates.reloadAsync()
useEffect(() => {
}, [])

Log in to Expo account

eas login
eas update:configure
💡 The following process will configure your project to use EAS Update. These changes only apply to your local project files and you can safely revert them at any time.
✔ Configured updates.url to ""
✔ Configured runtimeVersion for Android and iOS with "{"policy":"sdkVersion"}"
All builds of your app going forward will be eligible to receive updates published with EAS Update.
✔ Configured eas.json.
🎉 Your app is configured to use EAS Update!

Publish an update

eas update --branch production --message "Test-updating the app"


undefined is not a function with getRandomValues()

TypeError: undefined is not a function
at getRandomBase64 (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5840084)
at getRandomValues (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5840386)
at anonymous (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:4949155)
at anonymous (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:4949207)
at [Symbol.replace] (native)
at replace (native)
at uuid4 (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:4949062)
at captureException (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5020307)
at anonymous (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5009819)
at withScope (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5020158)
at anonymous (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:5009658)
at reportFatalError (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:162151)
at __guard (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:182465)
at callFunctionReturnFlushedQueue (address at /data/user/0/com.navienapp/files/.expo-internal/dd11be6f17c8cdcc4fc2cdcb541ac3fd:1:18146

The error you're encountering in your React Native Expo app when generating UUIDs seems to be related to the getRandomValues function, which is a part of the Web Crypto API. The specific error message TypeError: undefined is not a function at getRandomBase64 suggests that the function necessary for generating random values (used in UUID generation) is not available or not functioning as expected in the environment on the OnePlus 10 Pro NE2213 device.

Understanding the Error

  1. Crypto API Availability: The Web Crypto API, which includes getRandomValues, is a standard in modern browsers and environments but might not be available or fully compatible in all JavaScript environments, especially in certain mobile contexts.
  2. Device-Specific Issue: Since this issue is occurring on specific devices like the OnePlus 10 Pro NE2213, it could be due to the way the JavaScript environment or the React Native bridge is set up on those devices.


Use a Polyfill: If getRandomValues is not available, you can use a polyfill to provide an alternative implementation. This can ensure compatibility across different devices. For instance, you can use a library like react-native-get-random-values, which is a polyfill for the Web Crypto API in React Native.

npm install react-native-get-random-values

Then, import it at the top of your entry file (e.g., index.js):

import 'react-native-get-random-values';

NoMethodError - undefined method Error

NoMethodError - undefined method `=~' for ["-ObjC", "-w"]:Array

Ruby 3.2. A recent update had removed the =~ method for arrays, which was still being used by my version of Cocoapods (1.11.2). This method is typically used for matching regular expressions, and its sudden absence was causing the pod install process to fail.

gem uninstall cocoapods
gem install cocoapods
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