Thanks to a UX Designer, applications are much easier to use for the users and it is easy for the users to find their way around.
UX designer designs the user interface in such a way as to make it comfortable to use and easy for users to find their way around.
Deals with the graphical design of the user interface and its controls with specific regards to ergonomy.
Ergonomical user interface
Effectiveness of the ergonomy measures
Developer, Consultant (often, though not exclsively, related to web development)