1. An apparatus for switching a mobile user device between applications accessed over a computer network, the apparatus comprising: a processor; and one or more stored sequences of instructions which, when executed by the processor, cause the processor to carry out the steps of: providing authentication information, via the mobile user device, to enable access to an application; receiving on the mobile user device an authentication key authenticating access to the application; storing an application page for the application in the mobile user device in response to a user indication, via the mobile user device, to navigate away from the application; displaying the stored application page on the mobile user device in response to a user indication to navigate back to the application; and sending the authentication key from the mobile user device to reenable access to the application.