Handhelds shopping checklist

Platform
Palm OS and Microsoft's Windows Mobile OS currently rule the market for handhelds. Depending on your needs, narrow down your choices by selecting a suitable platform. Palm OS devices are generally easier to pick up with their clean and uncluttered interfaces. Pocket PCs are multimedia powerhouses with the ability to multitask. Look out for the Microsoft's latest Windows Mobile 6 operating system which can be found in some of the newest handhelds. (Read our quick guide to handheld OS for more information.)

Screen
As the display takes up a large chunk of real estate on a handheld, choose carefully and check for dead or stuck pixels. (Tip: When buying a PDA, it is always advisable to install the battery and switch on the handheld to check for dead pixels at the shop. This way, if there are dead pixels on the display, you can change it immediately. As the dead-pixel policies for many of the PDA companies differ, it can be quite a hassle asking for a change if you discover dead pixels after you leave the shop.) Most Pocket PCs have standard 320 x 240-pixel displays, while Palm offers different resolutions. The higher the display resolution, the better the viewing comfort. Handhelds such as the O2 Xda Flame and Dopod U1000 offer one of the highest resolution displays today at 640 x 480 pixels.

CPU
Most handhelds are powered by ARM architecture-based processors. These commonly range from 200MHz up to 624MHz. The most well-known of these is probably the Marvell XScale brand once owned by Intel. Other handheld chips currently found in the market include those from Samsung and Texas Instrument. If you plan to use your PDA for multimedia purposes, it's best to go for one that has a higher processing horsepower. However, if you are using it mostly for its organizer features, the handhelds with the midrange processors are the better bet because they will most likely be less expensive. Don't make your decision on numbers alone too. Some users find that even with the same speed, a certain brand's chip may outperform another's--always try them out at shops, or consult users from message boards first.

Memory
It used to be the case that whenever you let your PDA run out of battery, everything's lost. This was because data and applications were stored in the RAM--memory which requires power to hold information--while only the OS was stored in the ROM, which works somewhat like your USB drives, retaining data even when unplugged.

These days, there's persistent storage. All information is stored in the ROM, including applications. The RAM is where applications are run from, not unlike what happens on a desktop PC. So, the more RAM you have, the more tasks you can perform at once. Look out for at least 64MB of RAM for your next PDA, while ROM can vary greatly, from 64MB up to even 1GB like in the O2 Xda Atom Life.

Expansion
Handhelds these days offer a variety of memory expansion options. The smaller PDAs come with miniSD or microSD slots, though the latter is now more widespread. These are all variants of the Secured Digital (SD) format, and can be put into appropriate adapters and then read using an SD card reader. Do take note that some PDAs accept flash card capacities up to a certain storage limit, so if you are planning to increase the onboard memory, this is one detail you should clarify.

Connectivity
Bluetooth and USB are pretty much standard features on most handhelds these days. With the proliferation of Wi-Fi hotspots, it may be worth considering handhelds with integrated wireless LAN for high-speed Web surfing. A good number of PDAs such as the Asus P526 and E-Ten X500+ also come with onboard GPS support which is great for those who travel frequently. Most of the current PDA-phones in the market offer 3G support, though some lower end models offer only up to GSM triband or quadband options.

Camera
Make sure the capture resolution is at least 1.3 megapixels to be useful. If you're expecting to print those images, choose one with a 1.3- to 2-megapixel camera such as the Dopod D810. Increasingly, PDAs come with video recording and playback, too. Like mobile phones, the onboard flash lights on some PDAs typically offer minimal illumination but can double as useful torchlights.

Synchronization
As the PDA is an extension of your desktop, make sure it synchronizes with your PC or Mac. While Pocket PCs generally don't come with Mac support, you can work around it with third-party software such as PocketMac.

Power
If possible, always select a PDA that uses removable Lithium cells. This way, you have the flexibility to purchase additional batteries when your current one is defective, saving you a trip to the service center. You also have the option to buy a spare if you travel frequently.