Centralized authentication systems are provided. A representative system, among others, includes a mobile authentication registration system, a content provider and a wireless internet server. The mobile authentication registration system resides on a content provider which is coupled to the internet, and is operable to receive a single identification number and password from a user independent of a platform the user is associated with, and determine that the identification number and password combination provided by the user is associated with a registered user. The content provider provides personalized internet content to any of a plurality of registered users on a plurality of platforms. The wireless internet server receives a connection request from a wireless device, sends an authentication request to the mobile authentication registration system, and provides a personalized internet content from the content provider to said at least one wireless device. Methods and other systems for multiple access portals are also provided.