Microsoft Authenticator - APK, Download
Microsoft Authenticator is Microsoft's official two-step authentication app that lets you securely sign in to any service or app.
To use Microsoft Authenticator, you must sign in with a Microsoft email account (Hotmail, Outlook, or Skype ID will also work). Once you are signed in, you can use the two-step authentication process for other services.
Microsoft Authenticator is a great alternative to two-step authentication from Google. It also has a simple and clean interface.