An authentication system uses authentication tokens to allow access by third party applications to a printing device. A mobile device includes a mobile application that scans a graphical code to obtain identification information for the printing device. The mobile application requests that the third party application generate an authentication token. The mobile application stores the authentication token for the third party application and the identification information at a document processing platform, which is separate from the printing device or application. The printing device provides its identification information to the document processing platform to receive the authentication token. The printing device provides the authentication token to the third party application to establish a connection to process print jobs through the mobile device.