The Niehaus wireframe helps designers keep track of the user focus and not get carried away by the variety of tools and alternatives. The wireframe concept is ideal for new conceptions, independent landing pages and relaunches."

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When you move to electronic prototyping, there's a second way to improve your efficiency: use the same electronic tool throughout. I often see design teams start their prototyping effort with tools like Keynote and Balsamiq, move to Photoshop or Fireworks to create prototypes with higher visual fidelity, then turn to Dreamweaver or Flex to add interactivity for final usability testing.