Two-factor authentication adds an extra layer of security to users' Google Apps accounts by requiring them to enter a verification code in addition to their username and password when signing into their account. The two-step verification process prevents unauthorized access if someone obtains a user password.
Previously, users had to opt to receive a text message or phone call to get an authentication code, or alternatively use the Google Authenticator mobile app, which generates time-limited numerical codes that users needed to enter into their account log-in page.
The change, which is being rolled out from today, means that when a user tries to sign into a Google account with two-step verification enabled, a notification from the Google search app now asks if they are trying to sign in. A simple tap on the option "Yes, allow sign-in" quickly authenticates the account.
To enable two-factor authentication, users need to sign into Google's My Account section and select Google prompt under Sign-in & Security -> Signing in to Google -> 2-Step Verification.
Google notes that the option requires a data connection to work, and that it may take up to three days for the feature to appear across all account pages.
The Google app is a free download for iPhone and iPad available on the App Store. [Direct Link]