Consultants, students, and others with multiple accounts in Azure AD can add each account to Microsoft Authenticator and use passwordless phone sign-in for all of them from the same iOS device. You can enable passwordless phone sign-in for multiple accounts in Microsoft Authenticator on any supported iOS device. Enter the number they see on the login screen into Microsoft Authenticator dialog.To complete the sign-in process in the app, a user must next take the following actions: People who enabled phone sign-in from Microsoft Authenticator see a message that asks them to tap a number in their app. This technology can also be used with any app or website that integrates with Microsoft Authentication Libraries. This authentication technology can be used on any device platform, including mobile. Windows Hello for Business uses a similar technology. Microsoft Authenticator uses key-based authentication to enable a user credential that is tied to a device, where the device uses a PIN or biometric. Microsoft Authenticator can be used to sign in to any Azure AD account without using a password.

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