Personal digital assistant

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Image:Palm tungsten.jpg Image:Axim51v.jpg Personal digital assistants (also called PDAs) are handheld devices that were originally designed as personal organizers, but became much more versatile over the years. A basic PDA usually includes date book, address book, task list, memo pad, clock, and calculator software. Newer PDAs also have both color screens and audio capabilities, enabling them to be used as mobile phones, web browsers or media players. Many PDAs can access the Internet, intranets or extranets via Wi-Fi, or Wireless Wide-Area Networks (WWANs).

1 Functionality
2 Overview
3 Increasing popularity
4 Popular Consumer PDAs
5 Rugged PDA for Business, Government and Military Applications
6 See also
7 External links

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Functionality

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Touch screen

Many original PDAs, such as the Palm Pilot, featured touch screens for user interaction, having only a few buttons usually reserved for shortcuts to often used programs. Touch screen PDAs, including Windows Pocket PC devices, usually have a detachable stylus that can be used on the touch screen. Interaction is then done by tapping the screen to activate buttons or menu choices, and dragging the stylus to for example highlight text.

Text input is usually done in one of two ways:

Using a virtual keyboard, where a keyboard is shown on the touch screen. Input is done by tapping the letters.
Using letter or word recognition, where letters or words are written on the touch screen, and then "translated" to letters in the currently activated text field.

PDA's for business use, including the BlackBerry and Treo, have a full keyboard and scroll wheel or thumb wheel to facilitate data entry and navigation.

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Synchronization

An important functionality for PDAs is the possibility of synchronizing data with a contact database, such as Microsoft Outlook or ACT!, hosted on a personal computers or corporate server. The data synchronized ensures that the PDA has an accurate list of contacts, appointments and e-mail, allowing users to access the same information on the PDA as the host computer.

The synchronizing also prevents the loss of information stored on the device in case it is lost, stolen, or destroyed. Another advantage is that data input is usually a lot quicker on a personal computer, since text input via a touch screen is still not quite optimal. Transferring data to a PDA via the computer is therefore a lot quicker than having to manually input all data on the handheld device.

Most PDAs come with the ability to synchronize to a personal computer. This is done through synchronization software provided with the handheld, such as HotSync Manager, which comes with Palm OS handhelds, or Microsoft ActiveSync, which comes with Windows Mobile handhelds.

These programs allow the PDA to be synchronized with a personal information manager. This personal information manager may be an outside program or a proprietary program. For example, the BlackBerry PDA comes with the Desktop Manager program which can synchronize to both Microsoft Outlook and ACT!. Other PDAs come only with their own proprietary software. For example, some early Palm OS PDAs came only with Palm Desktop while later Palms such as the Treo 650 has the built-in ability to sync to Palm Desktop and/or Microsoft Outlook. Third-party synchronization software is also available for many PDAs from companies like Intellisync and CompanionLink. This software synchronizes these handhelds to other personal information managers which are not supported by the PDA manufacturers, such as GoldMine and Lotus Notes.

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Customization

Like a personal computer, it is possible to install additional software on most PDAs. Software can be bought or downloaded from the Internet, allowing users to personalize their PDAs to their liking. Some PDAs also allow for adding hardware. The most common is a memory card slot, which allows the users to get additional and exchangeable storage space on their handheld devices. There are also miniature keyboards that can be connected to some PDAs for quicker text input. PDAs with Bluetooth can also use Bluetooth devices like headsets and foldable keyboards with their PDAs.

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Other functionality

Other functions are commonly added to PDAs. Some examples are:

Audio recording
Camera functionality, allowing users to take photos or short video clips
Map functionality, with a GPS receiver for localization
Cell Phone functionality, which lets users make and receive phone calls, SMS and MMS messages.
Media Player abilities

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Ruggedized PDAs

For many years businesses and government organizations have relied upon rugged PDAs for mobile data applications. Typical applications include supply chain management in warehouses, package delivery, route accounting, medical treatment and record keeping in hospitals, facilities maintenance and management, parking enforcement, access control and security, capital asset maintenance, meter reading by utilities, and "wireless waitress" applications in restaurants and hospitality venues.

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Overview

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History

The term "personal digital assistant" was coined on January 7, 1992 by then Apple Computer CEO John Sculley at the Consumer Electronics Show in Las Vegas, Nevada, referring to the Apple Newton. Earlier devices like the Psion and Sharp Wizard already had the functionality to be considered PDAs, however. In fact, PDAs by other names were available as early as the mid-1970s -- first as very advanced calculators, then as electronic organizers, and later as palmtops. [1].

PDAs are some times referred to as "Palms" or "Palm Pilot" after an early PDA created by Palm, Inc. This usage is a case of genericized trademark, similar to referring to a tissue as a "Kleenex", a bandage as a "Band-Aid", or a pen as a "Biro".

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OS

The currently major PDA operating systems are:

Palm OS - owned by Palm, Inc.
Windows Mobile (Pocket PC), (based on the Windows CE kernel) - owned by Microsoft
RIM for the BlackBerry - owned by Research In Motion
Many operating systems based on the Linux kernel - free (not owned by any company) These include:
- GPE - Based on [[GTK+]]/X11
- OPIE/Qtopia - based on Qt/E Qtopia is developed by Trolltech, OPIE is a fork of Qtopia developed by volunteers
Symbian OS (formerly EPOC) owned by Ericsson, Panasonic, Nokia, Samsung, Siemens and Sony Ericsson

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Architecture

Many PDAs run using a variation of the ARM architecture (usually denoted by the Intel XScale trademark). This encompasses a class of RISC microprocessors that are widely used in mobile devices and embedded systems, and its design was influenced strongly by a popular 1970s/1980s CPU, the MOS Technology 6502.

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Increasing popularity

According to a Gartner market study, the overall market for PDAs grew by 20.7% in the third quarter (Q3) of 2005, compared to Q3 2004, with marketshare resolving as follows (by operating system):

Palm OS for Palm, Inc. PDAs and some other licensees- 14.9% (declining)
Windows Mobile for PDAs that comply with the Microsoft's Pocket PC specifications - 49.2% (increasing)
RIM BlackBerry for BlackBerry PDA (produced by Research In Motion) - 25.0% (increasing)
Symbian OS - 5.8% (increasing)
Various operating systems based on the Linux kernel for various special designed PDAs (many other supported) - 0.7% (stable)
Other - 4.4% (stable)

The reason usually cited for the resumption in PDA market growth (after market declines in 2002 - 2004) is the growing interest in PDAs as Personal Communicators offering wireless email capabilities (such as BlackBerries), and PDAs with built-in GPS capabilities for navigation. It is possible that Smartphones, mobile phones with PDA-like abilities, will curtail growth in the sales of PDAs without telephony capabilty in the near future, as they subsume more of the same functions.

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