1. A system for form filling an address on a space-constrained computing appliance, comprising: a server connected to a network, the server having access to at least one processor and a data repository, the server comprising a non-transitory physical medium; and program code executable from the non-transitory physical medium, the program code when executed by the processor causes the processor to perform a process comprising the steps of: establishing a client-server connection between the server and at least one user-operated computing appliance connected to the network, the user-operated computing appliance having a space-constrained display; initiating and maintaining an active data session between at least one user operating the computing appliance through a graphical user interface (GUI); storing a database of zip codes with associated cities and states on the user-operated computing appliance; responsive to the user initiating an order from the computing appliance, detecting when the user enters a zip code into a zip code field, wherein a city code field and a state code field are hidden until the user has entered the zip code into the zip code field, wherein the detection that the user has entered the zip code is determined based on a user action selected from the group consisting of: the user completely entering the zip code into the zip code field, the user entering the zip code into the zip code field and invoking a next command, and the user entering the zip code into the zip code field and invoking an enter command; looking up the entered zip code in the database of zip codes; retrieving an associated city and state information to generate a complete address, wherein the hidden city code field and the hidden state code field are displayed in a same field location as the zip code field and simultaneously auto-populated with the associated city and state information retrieved based on the entered zip code; and responsive to the user completing the order from the computing appliance, generating the complete address.