What two-factor authentication third-party applications are supported?

Our two-factor authentication service is a TOTP, aka a time-based one-time password solution. We recommend using it with third-party apps like Authy or Google Authenticator. For newer Apple devices, you can set up two-factor authentication using your device settings.
Authy <https://authy.com/>
Google Authenticator <https://myaccount.google.com/security>