When Less Is Less

The TwitterPeek, a little blue device that looks like a pocket calculator with too many buttons, does nothing but manage your twitter streams. It belongs to an electronic breed that rarely succeeds but never quite disappears: single-purpose devices. From the days of the Apple (AAPL) II on, general-purpose computers have mostly sent more specialized products like these packing. Versatile smartphones, likewise, have demolished the market for Palm's (PALM) and other nonphone PDAs.

Yet some single-purpose devices survive and—in the case of Amazon.com's (AMZN) Kindle and other electronic book readers—even thrive in a multipurpose world.

Reflecting on the TwitterPeek, a seriously flawed device, helped me figure out the secret of specialized success, and it's really quite simple. To have a chance, a specialist must do whatever it does much better than the same function on a more versatile product. Being cheaper won't do it, and neither will simplicity. The key is being better.

Startup company Peek began by offering low-cost wireless devices that provided minimal wireless e-mail for $19.95 a month. I could make a case for an e-mail-only handheld, but a product that does only Twitter is much harder to justify, even if it costs just $200 with lifetime wireless service (or $99 with six months of service, then $7.95 a month). Furthermore, TwitterPeek is far worse at Twitter than Tweetie on the iPhone, ÜberTwitter on BlackBerry (RIMM), or any other Twitter app I've tried. To me, the real value of Twitter is in the links included in tweets, but TwitterPeek's text-only browser leaves many Web pages unreadable.

WikiReader is an even odder single-purpose product. It's a $100 handheld that holds a subset of Wikipedia. It has no Internet connection, so the content loaded onto the device is what you get. There are no illustrations, and links are difficult to navigate. In other words, it's a pale shadow of the real Wikipedia on a PC or even a smartphone.

Some of the single-purpose devices, however, do make sense. My iPhone and BlackBerry take decent enough pictures, but I still own both point-and-shoot and single-lens-reflex cameras. They do nothing but take pictures—video, too, on the point-and-shoot—but they do it vastly better than any phone. I care about pictures, so I carry an extra device.

I can read Kindle books on an iPhone and now on a laptop, but I much prefer the Kindle reader. Simply put, the laptop is too big, the iPhone too small. The Kindle is easy on the eyes, comfortable to use anywhere, and if I turn off the wireless function when I don't need it to download books, the battery can last for weeks.

Flip video cameras from Cisco Systems (CSCO) are an interesting tweener case. Even the humblest model takes better pictures than a phone camera and is easier to use. But the gap is narrowing, and it's not clear to me that the elegant Flip is so superior to smartphones that it can survive.

Aside from the iPhone-like Touch, iPods are another example of specialized devices whose era may be ending because they cannot maintain their edge of excellence. Many smartphones now equal the iPod as music players and are better at showing photos and videos. Adding a mediocre video camera to the iPod Nano just isn't enough.

The lesson is that for a specialized device to cut it against more versatile competition, it must hit a high bar for excellence. A decade ago, the PalmPilot crushed the Apple Newton: While it did less, it did it much better. Eventually the Palm, too, was vanquished as smartphones subsumed its functions. Someday e-book readers and cameras may go the way of the PDA and the dedicated word processor. But at least for now, they can depend on the loyalty of delighted users.

For past columns and online-only reviews, go to businessweek.com/go/techmaven/

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