Azure Active Directory B2C.
Stay connected with your consumers with a cloud identity service that is reliable and cost effective. Built on Azure Active Directory, the cloud identity platform that handles billions of authentications per day, Azure Active Directory B2C is a highly available, global, identity management service for consumer-facing applications that scales to hundreds of millions of identities. It can be easily integrated across mobile and web platforms. Your consumers can log on to all your applications through fully customizable experiences by using their existing social accounts or by creating new credentials.