Twitter allows its users to sign in, log in, or create accounts with other websites and mobile apps by using the "Sign In With Twitter" feature that you've probably seen implemented before.
This sign-in functionality is similar to Sign In with Facebook or Google's login button.
It makes accessing and interacting with your website or mobile app very convenient for users. Users don't have to take the time to create a new account since their already-existing Twitter account can be used for verification and credential validation.
When a user clicks "Sign in with Twitter" an authorization page will open where a user is prompted to enter the Twitter username or email address as well as password and sign in:
Here's what the authorization page looks like. Each of the mentioned components is highlighted.
If you're considering providing the Twitter sign-in button on your website and/or mobile app, there are a few requirements for implementation when it comes to privacy issues.
Must disclose when and how you add location information to users' Tweets.
The Twitter Developer Policy includes a section titled "Respect Users' Control and Privacy" that includes these requirements for privacy protection.
Twitter requires that express consent is obtained before your app interacts with users' Twitter accounts in certain ways, such as:
Or using a user's content to promote a commercial product or service
If your website or mobile app wishes to take any of the actions listed above after users have logged in via Twitter, make sure that you request consent from the user.
This consent can be asked at the time the user's prompted to enter the Twitter information for sign-in.
Here are a number of examples of websites and mobile apps that use Twitter sign-in, how they use the sign-in button, and how they have adjusted their Privacy Policies to meet these legal requirements.
Medium offers an option for users to "Continue with Twitter" rather than having to create an actual Medium account using only their email addresses.
In the "Continue with Twitter" button, Medium lets users know that "we won't post without asking."
Fine print at the bottom of this screen informs users of what will happen if they sign up with Twitter, and provides a link to a Login FAQ with additional information.
Klout has very basic links on its homepage for Facebook, Twitter, and the standard sign-up using the email address.
Klout users are told that when they:
Hootsuite also has a standard "Sign in with Twitter" button, along with "Sign in with Facebook" and "Sign in with Google":
This helps users understand how they can have the ability to really control what data is collected, shared and used by Hootsuite.
Product Hunt requires users to log in through either Twitter or Facebook and makes it clear on the login page that no posts will ever be made to either service without permission.
Goodreads provides options for signing into or creating an account, as well as the option to sign in using Twitter. Instead of buttons, icons are used.
Allowing users to sign in to a website or mobile app via a Twitter sign-in is a very common and convenient thing to do.