A reverse two-factor authentication system comprising: a processor; a computer storage medium comprising computer executable instructions embodied thereon that when executed by the processor configure the system to: detect, at a first time instance, that a first computing device is within a threshold distance of a second computing device, the second computing device including a service or app for which authentication is required; determine that the first computing device is associated with at least one device authentication credential indicating that the first computing device was utilized by a registered user upon registering for access to the service or app; receive, at the second computing device, the at least one device authentication credential; after receiving the at least one device authentication credential, receive, at the second computing device, at least one user credential associated with a user of the second computing device; verify, at the second computing device, that the at least one user credential is associated with the registered user; and permit the user of the second computing device to access the service or app, wherein registering for access to the service or app comprises: transmitting a code from a server to the second computing device, receiving, at the first computing device, the code inputted by the user of the second computing device, and receiving, at the server, the code from the first computing device and, in response, generating the at least one device authentication credential, wherein the at least one device authentication credential associates identifying details associated with the first computing device with user credentials of the registered user. a processor; a computer storage medium comprising computer executable instructions embodied thereon that when executed by the processor configure the system to: detect, at a first time instance, that a first computing device is within a threshold distance of a second computing device, the second computing device including a service or app for which authentication is required; determine that the first computing device is associated with at least one device authentication credential indicating that the first computing device was utilized by a registered user upon registering for access to the service or app; receive, at the second computing device, the at least one device authentication credential; after receiving the at least one device authentication credential, receive, at the second computing device, at least one user credential associated with a user of the second computing device; verify, at the second computing device, that the at least one user credential is associated with the registered user; and permit the user of the second computing device to access the service or app, wherein registering for access to the service or app comprises: transmitting a code from a server to the second computing device, receiving, at the first computing device, the code inputted by the user of the second computing device, and receiving, at the server, the code from the first computing device and, in response, generating the at least one device authentication credential, wherein the at least one device authentication credential associates identifying details associated with the first computing device with user credentials of the registered user. detect, at a first time instance, that a first computing device is within a threshold distance of a second computing device, the second computing device including a service or app for which authentication is required; determine that the first computing device is associated with at least one device authentication credential indicating that the first computing device was utilized by a registered user upon registering for access to the service or app; receive, at the second computing device, the at least one device authentication credential; after receiving the at least one device authentication credential, receive, at the second computing device, at least one user credential associated with a user of the second computing device; verify, at the second computing device, that the at least one user credential is associated with the registered user; and permit the user of the second computing device to access the service or app, wherein registering for access to the service or app comprises: transmitting a code from a server to the second computing device, receiving, at the first computing device, the code inputted by the user of the second computing device, and receiving, at the server, the code from the first computing device and, in response, generating the at least one device authentication credential, wherein the at least one device authentication credential associates identifying details associated with the first computing device with user credentials of the registered user. transmitting a code from a server to the second computing device, receiving, at the first computing device, the code inputted by the user of the second computing device, and receiving, at the server, the code from the first computing device and, in response, generating the at least one device authentication credential, wherein the at least one device authentication credential associates identifying details associated with the first computing device with user credentials of the registered user.