When he parks his car, author Timothy Ferriss snaps a photo of the nearest cross streets with his camera phone. In business meetings, he'll often take pictures of sketches and notes made on a whiteboard. When he's out for dinner, he'll whip out the phone again to capture an image of the label on the wine he's drinking. He never knows when he'll want to recall the data later.

Ferriss, a productivity expert, blogger, and author of the best-selling book The 4-Hour Workweek, then ships those photos to what he calls his "augmented brain," which exists not in his head, but on the Web.

He is one of a growing number of people using a Web-based service and software application running on smartphones and PCs called Evernote that is quickly becoming a receptacle for much of the ephemera that otherwise gets cluttered and sometimes lost in a person's busy life.

At first, Ferriss resisted the suggestion from readers of his blog that he try the application. "I have this philosophical stance where I tend to avoid accumulating new gadgets and software because usually they create more work than they are meant to prevent," Ferriss says. But when a few reader suggestions turned into dozens, he decided to try it. "At first it wasn't clear what the appeal was. But the more I used it, it became really clear why they liked it."

Word Recognition in Photos

Founded by Stepan Pachikov, who co-founded handwriting recognition software company Parascript and is a former vice-president of Silicon Graphics, Evernote is designed for people struggling to become more organized. A February survey by the National Association of Professional Organizers, a trade group, found that 96 percent of some 400 adults said they could save time every day if they were better organized. "No one remembers everything as well as...