An interface design tool (IDT) is used for creating the user interface of a software application. This kind of tool provides features that help in the prototyping of a software application, and the level of prototype fidelity depends on the features provided by the tool. It helps in visualizing the look and feel of an application and is used by designers to determine requirements and obtain feedback from users. This tool can be used to create a user interface (UI) layout, graphics design, sketches and mockups. The tool may be a Web-based plugin or a vector-based tool, and sometimes even Microsoft PowerPoint can be used as an interface design tool.
There are many user interface design tools available on the market, which vary in the level of prototype fidelity they provide and in the features they provide for creating designs. Some of the types of UI designs that can be produced with these tools include diagrams, illustrations, wireframes, mockups and screen designs.
UI design tools can be generally classified according to the level of fidelity. Fidelity refers to the closeness of resemblance the prototype has to the actual application. Low fidelity may refer to two-dimensional diagrams, pencil sketches and storyboarding that are static. High fidelity refers to prototypes that are functionally more powered, providing extra functions like navigating around the application and interactive demonstrations on the how the application works.
Some interface design tools are also capable of generating code from the UI design that has been created. Some tools can also be used to create templates for websites and generic applications.
These design tools find a useful application in usability testing and customer validation. They can be used for creating simulations of the application and give an overall idea of how the finished product will look. They eliminate misunderstandings in the requirements specification and thus eliminate any extra costs incurred in the later stages of development due to incorrect capture of requirements.