Set up Twitter 2-Step Verification to Work With Third-Party Apps
If your Twitter account is configured with two-factor authentication (which you definitely need, and if not, you should set it up right now), then now you don’t need to use SMS to access your account. …
You can now use a third party app like Google Authenticator, Duo Mobile, or Authy. This can be especially useful if you are in someplace like another country (or your friend’s office) where you don’t have a cellular signal and want to log into your account.
To set up a third-party authentication app, you first need to change your Twitter settings from SMS, which is enabled by default, to a security app. To do this, click your Twitter profile icon and select Settings. From there click on Account and then Security. In this menu, you will see that text message is enabled by default. Tap Change to turn it off, and then turn on the Security app feature (below it) instead.
To set up a standalone third-party app, in the top menu, click your profile icon, then click Settings & Privacy, then select the Account tab. Click on Review Login Verification Methods to get started. You will be prompted for your Twitter password. Then click “Configure” and follow the instructions on the screen.
Eventually you will see a pop-up window with a QR code. You will need to scan a QR code in the authenticator app to link it to your Twitter account. Your app will then provide you with a 6-digit numeric security code that you will need to enter on Twitter to complete the connection.
One Lifehacker writer also reported that after disabling text two-factor mode, he had to re-enable it before I could enable mobile-based two-factor mode. If you run into problems along the way, try this.
The whole process definitely takes a few minutes, but it’s worth it.