Here is a partial list of tools that will assist with the prototyping process, broken down by the phase they are best suited for all phases
The following list contains the software that you are going to use throughout the entire prototyping process, as they are the basic tools for writing documents, make draws and sketches, and create diagrams and presentations.
Microsoft Office/Open Office: This is essential for documentation throughout the project. MS Office is available for a price from the Microsoft website. Open Office is free and open source and includes many of the features in MS Office.
PowerPoint: This is useful for wire frame mock ups and quick proof of concepts. It is included in MS Office and Open Office has an equivalent application in its bundle.
Visio: This is an excellent tool for creating flow charts, placeholder graphics, screen mock ups, and wireframes. It is available for a price from the Microsoft website. Open Office contains a similar application for free tools...