A system for use with a mobile cellular device comprising an Internet browser and an embedded subscriber identity module (“eSIM”) card. The eSIM card stores an application and a first profile. The system includes a web server configured to generate a web portal comprising a plurality of service plans. The first profile establishes communication over a first network with the web server, which transmits the web portal to the Internet browser over the first network. The web portal receives a selection of one of the service plans from the Internet browser. The web server sends the selection to a subscription manager configured to select an operational profile based on the selection and cause the operational profile to be transmitted to the application. The mobile cellular device is configured to communicate over a second network using the operational profile after the operational profile has been received and activated by the application.