When it comes to technology, sometimes less is indeed more. In response to customers overwhelmed by the multitude of functions performed by such products as the iPhone and Samsung's Blackjack, a number of companies have responded by developing products that focus solely on one particular feature. One of the more prominent examples of this is GreatCall's Jitterbug phone, which, amazingly, does one thing: handle phone calls. GreatCall founder Arlene Harris, the 'First Lady of Wireless,' has a long background in cell phones. Jitterbug, which still features only a few large buttons, began in the mid-1990s as a safety device for roadside emergencies. Strangely, though, simplicity comes at a premium: Jitterbug costs substantially more than, to use one example, Samsung's Blackjack. Other devices capitalizing on customers' desire for streamlined functionality include Apple's iPod Shuffle, which, although lacking a screen, has sold approximately 30 million units in less than three years; and a variety of e-mail printers which can receive and send hard copies of messages, along with photo attachments. (Outgoing messages are scanned and converted to PDF files.) These e-mail printers are sold by such startups as Presto, Celery, and CaringFamily. The elderly are a key market for these devices, as they are motivated to stay in touch with relatives, while disinclined to master complicated, multifunctional devices. Thus, Jitterbug's features include live operators who will dial for you, and an instruction manual printed in large type. According to consultant Donad Norman, 'the real trick is not to get rid of the features but to make them effortless.'