Application based user management

Hello,

I'm looking for a best practice how-to enable a user management within an application. Basically there are two main roles within the target application:

• administrator role - I assume that one can be based on the appian built-in user management
• standard user role - thats a role where an "anonymous" user can apply for
  • with a self choosen username and password
  • based on an application built login interface such user will have some additional things to do

What would be a good way to achieve this if any?

Thank you in advance
Thomas