Systems, methods, and computer-readable storage media are provided for authenticating users to secure services or apps utilizing reversed, hands-free and/or continuous two-factor authentication. When a user desires to access a secure service or app for which s/he is already registered, the user, having a registered mobile computing device in proximity to his or her presence, comes within a threshold distance of a computing device that includes the desired secure service or app. The computing device authenticates the particular mobile computing device as associated with the particular registered user that utilized that mobile device during registration. Subsequent to such device authentication, the user is able to login to the service or app by simply providing his or her user credentials at a login form associated therewith. Two-factor authentication in accordance with embodiments hereof is more secure and more efficient that traditional authentication methodologies.