How to Buy a PDA

The Big Picture

Formerly just handy pocket secretaries, PDAs have become ever more versatile. Modern PDAs can handle wireless e-mail and instant messaging, digital photography, music, and even video. Increasingly, businesspeople who spend a lot of time on the road are replacing standard cell phones with PDA-phone hybrids such as a Palm Treo, a RIM BlackBerry, or a Windows Mobile-based model. (If you're interested in such a device, be sure to read "How to Buy a Cell Phone" as well.)

While PDAs of one type or another have been around for about a decade, technological advances have made them more versatile at the high end and more affordable at the low end. And these days, all PDAs, regardless of price, are thin, lightweight, and generally small enough to fit easily into a pocket.

The processors that power PDAs are faster than they used to be, so PDAs can now handle digital music and photos with ease. High-end models now sport mobile graphics processors that enable gaming and video playback without a huge sacrifice in battery life. At the other end of the price spectrum, even lower-cost units come with color screens. And a growing number of mid- and high-range units sport integrated mini-keyboards (also known as thumb keyboards), a welcome development for users who want to use their PDAs for e-mail or messaging and feel slowed down by styluses and handwriting-recognition software.

The ability to communicate wirelessly enhances a PDA's overall utility. Many of the midrange units incorporate 802.11b or the faster 802.11g Wi-Fi for accessing home or work networks or commercial hotspots. Even more PDAs are equipped with Bluetooth, which can connect to desktop or laptop PCs, to peripherals (such as headsets or printers), or to the Internet through a suitably equipped cell phone. One of the latest trends in PDAs is the inclusion of integrated GPS receivers and software that allows the handheld to double as a navigation device, either in a car or when you're walking around an unfamiliar city.

Key Features

Platform: Most PDAs run on one of two major operating systems, or platforms: the Palm OS from PalmSource (now a subsidiary of the Japanese firm Access) and Microsoft's increasingly popular Windows Mobile OS. Some devices run on other platforms--most notably Research In Motion's BlackBerry--but the Palm OS and Windows Mobile still dominate the market.

Though these platforms used to be distinct, the differences have diminished--to the point where Palm now makes its Treo PDA/phones for both Palm OS and Windows Mobile platforms. PDAs based on early versions of the Palm OS were simpler, lower-cost devices, and these days the most inexpensive Palms are still cheaper than the lowest-end Windows Mobile PDAs. But Palm's high-end models today match the Windows Mobile offerings in such features as cameras and Internet connectivity. And while all PDAs based on Windows Mobile used to be relatively expensive across the board, today you can find models that compete directly with midrange Palms.

Both are also taking on increasingly capable models based on the BlackBerry OS, which continues to set the gold standard for mobile e-mail management, and Symbian, the OS used by Nokia. The main drawback here is relative scarcity of third-party applications for these OSs; if you're content with the apps you get with these devices, this may not be a problem.

Windows Mobile vs. Palm OS: How you plan to use a PDA will best determine which operating system you choose. Palm OS-based devices, mostly found on PDAs from Palm, provide the simpler approach. Out of the box, Palm devices will synchronize appointments and contacts with the Palm OS's proprietary personal information manager desktop software, the Palm Desktop. Most Palm OS vendors also bundle a program that syncs your data with Microsoft Outlook. To create and edit Microsoft Office-compatible documents on a Palm OS device, you will need third-party software such as Dataviz's Documents to Go (bundled with some Palm devices) or Cutting Edge Software's Quickoffice.

Microsoft's Windows Mobile OS (the latest version is Windows Mobile 5, usually with a device-specific patch) basically looks like a considerably shrunken version of the desktop Windows OS. It can run numerous applications simultaneously--though only one app can appear on screen at a time. Unlike the Palm OS, which shuts down one application (or runs it in the background as appropriate) when you open another, Windows Mobile requires you to manually close an application or it will run in the background and use up memory you might want for other purposes. (The latest Windows Mobile devices have a memory manager that lets you see what applications are running and how much memory they are using.) Windows Mobile generally requires more memory than the Palm OS, so most Windows Mobile 5 PDAs come with at least 64MB of ROM and an equal amount of RAM.

The Windows Mobile OS is more complex to use than the Palm OS. But with most keyboard-equipped Windows Mobile devices, you also get pared-down versions of Microsoft Office apps such as Outlook, Word, Excel, and PowerPoint--letting you create and edit documents as you would on your desktop. When you synchronize your Windows Mobile PDA with your PC, documents on each are updated accordingly. The integrated Windows Media Player 10 in Windows Mobile 5 handles MP3, WMA, and other multimedia files; it also allows you to run content from subscription sites (such as Rhapsody) that use Microsoft's Digital Rights Management technology. A growing number of vendors are offering Windows Mobile devices. Hewlett-Packard has historically offered the greatest variety, but more competitors are emerging--particularly in the PDA/phone arena.

PDA CPUs: There was a time when nobody paid attention to PDA processors, in part because they were fairly low powered to conserve battery life, and also in part because they are embedded. In other words, you can't upgrade or replace them the way you might be able to swap out a chip on a PC motherboard. But the mobile CPU business has become more competitive, thanks in no small part to Intel's entry into the market (Intel sold its handheld chip business to Marvell several months ago). PDA vendors have begun to promote the chips that power their handhelds--and savvy buyers know that a powerful chip can make for snappy performance in a high-end device.

Intel's XScale ARM processors have been upping the ante in this arena. The latest processors--the PXA27x family, previously code-named Bulverde--can run at up to 624 MHz and are available either with or without integrated memory. Texas Instruments and Samsung also compete in the PDA processor market, with TI focusing primarily on connected devices. Following its acquisition of Intel's handheld processor unit, Marvell (previously best known as a Wi-Fi chip maker), is expected to compete vigorously as well.

Internal memory (RAM): Basic organizer functions (appointments, alarms, contact lists, tasks, and memos) don't require much memory. The 32MB amount that comes with the lowest-end current Palm--the $99 Z22--is adequate if these tasks are all you want to do. Third-party software such as utilities and games quickly eat up RAM, however, so look for a model with 64MB or more of RAM--or a model that accepts Secure Digital (SD) memory cards (see below)--if you plan to load lots of extra programs or you want to store lots of media for playback. Newer Palms include ROM for storing the OS and key vital data such as contacts, so that you don't lose them if the battery runs down.

Applications on Windows Mobile devices require more memory, especially to play audio or video. The specs for today's Windows Mobile PDAs usually specify two types of internal memory: RAM and flash-based ROM. The ROM is where the PDA stores the OS and vital data such as contact information. If your batteries run down and your device loses power, the data in ROM is unaffected. RAM, on the other hand, requires power--if you lose power, you lose data in RAM. Most software runs in RAM, so the more you multitask on a Windows Mobile PDA, the more RAM you'll want. Look for a unit with at least 64MB each of ROM and RAM.

Almost all Windows Mobile devices come with external card slots. CompactFlash used to be the dominant expansion format, but SD Card has become more common. Some models accept both CompactFlash and SD Card formats. These slots can also connect to add-ons such as cameras, audio players, phones, or GPS receivers.

Input (keyboard or stylus): The handwriting-recognition capabilities of Palm and Windows Mobile devices have improved over the years, and all PDAs that support handwriting recognition come with a virtual hunt-and-peck software-based keyboard. Some models with integrated thumb keyboards still support these traditional touch-screen input methods. However, Palm's Windows Mobile- and Palm-based Treos (phone hybrids with integrated keyboards) do not support handwriting recognition even though they have touch screens. Nor does the BlackBerry OS. Many users who want to use a PDA in place of a notebook have turned to one of several third-party add-on keyboards.

Screen type: Bright color screens have become the norm even for low-end PDAs, and screen resolution has become a differentiating factor: While Windows Mobile displays once laid claim to having the highest-resolution color screens (quarter-VGA, or QVGA, screens with 320-by-240-pixel resolution) --some Palm OS-powered PDAs now offer 320-by-320- or even 320-by-480-pixel resolution (compared with 160-by-160-pixel resolution on older or less expensive models).

Not all color screens are created equal: The screens on cheaper models generally aren't as crisp and sharp as those on more expensive units. That's why it's a good idea to check out the model you're considering in person before you buy.

Battery power: Modern PDAs include built-in batteries that you recharge by either placing the PDA in a docking cradle or, increasingly, hooking it up to a combination syncing/recharging cable. The battery life depends largely on the size and brightness of the screen, the applications you run, and whether you're using Wi-Fi (a big battery-life drain). Battery life can be anything from a couple of hours to 10 hours.

Cameras: Many current PDAs include built-in cameras similar to those found in camera phones. PDA cameras let you take a quick snapshot of something (or someone) in moderately bright light. Resolution ranges from VGA (640 by 480 pixels) to a growing number of 1- and even 2-megapixel models. But don't expect beautiful, Annie Leibovitz-quality photos with a PDA camera. In some cases, you'll be lucky if you can make out what you've snapped, even if the device includes an LED flash to illuminate the scene. But in a crunch, a PDA camera can be a useful feature.

GPS: With GPS-driven car navigation systems gaining in popularity, a couple of vendors (Garmin International, HP, and Pharos) have created PDAs with integrated GPS receivers and bundled navigation software, which provide voice-based turn-by-turn directions and maps. Typically you can't yet get both integrated GPS and integrated Wi-Fi in the same unit, but a small and growing number of devices are bundling both technologies--and sometimes Bluetooth and cell phone radios as well. If you want to add Wi-Fi or GPS, you should be able to do so via third-party products that connect either via Bluetooth (in the case of GPS) or through the handheld's expansion (SD) card slot.

RIM's BlackBerry: Research In Motion's BlackBerry devices use a fairly expensive BlackBerry Enterprise Server to synchronize e-mail and calendar items with major enterprise-collaboration environments such as Microsoft Exchange (Outlook) and Lotus Domino (Notes). BlackBerry devices can wirelessly send and receive e-mail, and a growing number of the models also double as cell phones.

Unlike most Palm and Windows Mobile devices, Blackberry PDAs use thumb keyboards and jog-wheel navigation.

Whatever your choice, try to kick the tires before you buy. Check to see how well you can read the screen with the backlight off--or outside on a sunny day. If the unit has a keyboard, try it out for size. Make sure the buttons are reasonably comfortable and solid. Fiddle with the navigation--how easy is it to do what you want to do?

If you're looking for a cell phone and a PDA, you should consider a PDA/phone so that you don't end up lugging around two separate devices. If you tend to be on the road a lot and need to check your e-mail regularly, you might also consider models that offer Internet access--through a built-in cell-phone modem, a Bluetooth connection to a cell phone, or built-in 802.11b or 802.11g Wi-Fi.