Hi David
Just trying to understand what you are after.
The applications you talk about are stateless all business logic and data comes from the back end.
Let's say we are making an application called "Profile Viewer", the whole point of the application is that you provide a username to the application and it loads up the profile of that username.
Wouldn't the retrieval of the users profile be a service call (or function)?
or are you talking about a header variable sent back after the users logon is validated?
Cheers
John P