O2 XDA Atom - one of the popular PDA products in Vietnam market.Photo: Breakingnewsblog
Most PDAs run on one of the two popular operating systems, Palm OS, from PalmSource (currently a subsidiary of Access - Japan) and Microsoft's Windows Mobile OS. Others use Research In Motion's Blackberry. BlackBerry devices using BlackBerry Enterprise Server software are quite expensive to synchronize schedules and e-mail with fairly common environments such as Microsoft Exchange / Outlook or Lotus Domino / Notes. BlackBerry can send and receive wireless e-mail, some new models have phone functions. Unlike Palm and devices running Windows Mobile, PDA brand Blackberry uses keyboard typing.
Windows Mobile has clearly demonstrated its power, to the point that Palm must produce hybrid devices that hang PDAs for those two operating systems. The early Palm OS PDAs were simpler, cheaper - the cheapest Palm machines now have less money than the lowest-end Windows Mobile PDA. But Palm's most advanced models are also compatible with Windows Mobile in features like cameras and Internet connectivity.
In general, the Windows Mobile operating system (the latest version, version 5) looks quite similar to Windows on the PC, being able to run multiple applications simultaneously, even if only one program appears on the screen when used. Meanwhile, Palm OS must turn off an application before it opens another application. And so, Windows Mobile needs more memory than Palm OS. PDAs using version 5 of this operating system often come with ROM and RAM about 64 MB.
2. CPU central processor
There was a time when people did not pay much attention to the processors, partly because they were so weak that they did not consume a significant amount of battery, because they were built in. This means that you cannot upgrade or replace them in the way of replacing the chip on the PC motherboard. But later, the CPU business became more competitive, partly because Intel jumped into this market. PDA vendors started promoting microprocessors that could make handheld devices more powerful. Knowledgeable consumers also find that strong chips will make the machine run better.
Intel's XScale ARM processor has been at the forefront of this field. The latest processor of the PXA27x family (formerly named Bulverde) can reach 624 MHz.
3. Memory
Basic organizational functions such as scheduling appointments, alarms, contact lists, to-do tasks, notes . do not take up much memory, only about 32 MB of RAM is enough. However, third-party software consumes memory, requiring you to have more RAM, about 64 MB or more, or type of external memory card acceptance.
Applications on devices running Windows Mobile require more memory, especially for playing audio or images. They usually have two types of internal memory: RAM and flash ROM. ROM memory is where PDA contains operating system and important data such as contact information. If the battery is low or the device suddenly "turns off", the data in the ROM is not lost. RAM requires energy - if the battery runs out, the data in it will be lost. The software runs on RAM so if you use many programs, you have to invest in RAM.
Most Windows Mobile devices have an expansion card slot. CompactFlash was once the "dominant" format but now SD cards (Secure Digital) become more popular. These slots also connect to attached devices such as cameras, MP3s, phones or GPS receivers.
4. Input device (keyboard or touch pen)
Handwriting recognition functions on current Palm and Windows Mobile devices have greatly improved. Almost all PDAs support handwriting recognition, which comes with a virtual keyboard. Some have real keyboards but still support how to input data on the touch screen. However, Palm's popular Treo line (keyboard hybrid phone) does not support handwriting recognition even though they have touch screens. Many customers who want to use PDAs to replace laptops find third-party keyboards.
5. Screen type
Bright-colored screens have become the norm, even for the lowest-level PDA. Screen resolution is the criterion that makes a difference in product lines. The screen on a Windows Mobile device was once considered to be the highest resolution (QVGA or 1/4 VGA with 320x320 pixels), but some Palm OS PDs now have the same or even resolution 320 x 480 pixels.
Not all color screens are the same. Screens on low-cost machines often produce sharp images with higher price. That's why you should check the model before you buy.
6. Battery
New PDAs always have a built-in battery charger or charging dock. Battery life depends on the size and brightness of the monitor, applications running on the device and whether the customer has Wi-Fi connection. This duration ranges from 2 to 10 hours.
7. Camera
Many PDAs now have built-in cameras like in mobile phones that use other photographic and video cameras. Users can shoot quite quickly with moderate brightness. Resolution ranges from VGA (640 x 480 pixels) to 1-2 megapixels. However, you should not expect good image quality like on a digital camera.
8. Global positioning GPS
With the success of the car navigation system, some of the most prominent companies, Garmin International, have built PDAs with GPS receivers and support software. Users will receive notification of voice directions and maps. However, consumers still do not have the opportunity to use GPS and Wi-Fi on a single machine. If you want both, use the third-party developer GPS receiver. Users can also connect the receiver to a PDA via a CompactFlash or SD Card slot, or Bluetooth.
In Vietnam market, PDA has appeared for a long time. The feature "brick" when the new launch costs tens of million. Weaknesses in poor phone reception have been overcome in many recent models. PDA players can look to O2, Pocket PC, iPaq, PalmOne . to manage their work in a convenient and efficient way, while expressing their "stylish" style.