---
title: Twitter login
slug: back4app/ivueL3X7Er_Ih5HXr5FXx
description: In this tutorial you learn how to add Twitter login to your ios app using Swift.
image: https://www.back4app.com/images/logo-social.png
createdAt: 2024-03-12T11:20:36.945Z
---
# Add Twitter login to your iOS App using Swift
## Introduction
This section explains how you can create an app with user registration using Twitter Login and [Parse Server core features](https://www.back4app.com/product/parse-server) through Back4App.
## Prerequisites
:::hint{type="info"}
**To complete this quickstart, you need:**
- [Xcode](https://developer.apple.com/xcode/).
- An app created at Back4App.
- Follow the [New Parse App tutorial](https://www.back4app.com/docs/get-started/new-parse-app) to learn how to create a Parse app at Back4App.
- An iOS app connected to Back4App.
- **Note: **Follow the [Install Parse SDK (ObjC) Tutorial](https://www.back4app.com/docs/ios/parse-objc-sdk) to create an Xcode Project connected to Back4App.
:::
## 1 - Twitter Set up
To start using Twitter functions, you need to:
1. Go to [Twitter Application Management Website](https://twitter.com/login?redirect_after_login=https%3A%2F%2Fdeveloper.twitter.com%2Fapps), sign in with a Twitter account and click on `Create New App`.
2. Add your application’s Twitter consumer key on your Parse application’s settings page.
3. When asked to specify a “Callback URL” for your Twitter app, please insert a valid URL like`http://twitter-oauth.callback.` This value will not be used by your iOS or Android application, but is necessary in order to enable authentication through Twitter.
4. Add the `Accounts.framework` and `Social.framework` libraries to your Xcode project.
5. Add the following where you initialize the Parse SDK, such as `inapplication:didFinishLaunchingWithOptions`:
```swift
1 PFTwitterUtils.initializeWithConsumerKey("YOUR CONSUMER KEY", consumerSecret:"YOUR CONSUMER SECRET")
```
## 2 - Login and SignUP
`PFTwitterUtils` provides a way to allow your `PFUsers` to log in or sign up through Twitter. This is accomplished using the `logInWithBlock` or `logInWithTarget` messages:
```swift
1 PFTwitterUtils.logInWithBlock {
2 (user: PFUser?, error: NSError?) -> Void in
3 if let user = user {
4 if user.isNew {
5 print("User signed up and logged in with Twitter!")
6 } else {
7 print("User logged in with Twitter!")
8 }
9 } else {
10 print("Uh oh. The user cancelled the Twitter login.")
11 }
12 }
```
When this code is run, the following happens:
1. The user is shown the Twitter login dialog.
2. The user authenticates via Twitter, and your app receives a callback.
3. Our SDK receives the Twitter data and saves it to a `PFUser`. If it’s a new user based on the Twitter handle, then that user is created.
4. Your`block` is called with the user.
## 3 - Twitter Linking
If you want to associate an existing `PFUser` with a Twitter account, you can link it like so:
```swift
1 if !PFTwitterUtils.isLinkedWithUser(user) {
2 PFTwitterUtils.linkUser(user, {
3 (succeeded: Bool?, error: NSError?) -> Void in
4 if PFTwitterUtils.isLinkedWithUser(user) {
5 print("Woohoo, user logged in with Twitter!")
6 }
7 })
8 }
```
The steps that happen when linking are very similar to log in. The difference is that on successful login, the existing PFUser is updated with the Twitter information. Future logins via Twitter will now log the user into their existing account.
If you want to unlink Twitter from a user, simply do this:
```swift
1 PFTwitterUtils.unlinkUserInBackground(user, {
2 (succeeded: Bool?, error: NSError?) -> Void in
3 if error == nil && succeeded {
4 print("The user is no longer associated with their Twitter account.")
5 }
6 })
```
## 6 - Twitter API calls
Our SDK provides a straightforward way to sign your API HTTP requests to the [Twitter REST API](https://dev.twitter.com/rest/public) when your app has a Twitter-linked `PFUser`. To make a request through our API, you can use the `PF_Twitter` singleton provided by `PFTwitterUtils`:
```swift
1 let verify = NSURL(string: "https://api.twitter.com/1.1/account/verify_credentials.json")
2 var request = NSMutableURLRequest(URL: verify!)
3 PFTwitterUtils.twitter()!.signRequest(request)
4 let task = NSURLSession.sharedSession().dataTaskWithRequest(request) { data, response, error in
5 // Check for error
6 // Data will contain the response data
7 }
8 task.resume()
```