We live in a digital era, but pen-and-paper still has its place. Twitter recently redesigned its mobile browser client for basic feature phones, but for creating mock-ups, its team still found drawing things on paper more useful to start the process than any form of digital tool.
In a blog post outlining the redesign process, Twitter notes the role that paper prototypes played:
We began the process by sketching out proposals for primary views and navigation. Next, we fleshed out details like the Tweet anatomy and interaction flows for tasks like tweeting, searching, and writing direct messages.
After that initial stage, Twitter's engineers concentrated on building actual code that could be tested on devices. But starting with a simple sketch made more sense than diving right into a web editor or layout designer. It's something to bear in mind any time you're starting on a design project.
Overhauling mobile.twitter.com from the ground up [Twitter Blog]