Tip Sheets

Personal Digital Assistants (PDA)

What are PDAs?

The term PDA is short for 'personal digital assistant', a handheld device that combines computing, telephone/fax, and networking features. PDAs are also called palmtops, hand-held computers and pocket computers.

The field of PDA development was pioneered by Apple Computer^TM, which introduced the Newton MessagePad in 1993. Shortly thereafter, several other manufacturers offered similar products.

A distinction should be made between PDAs and Notebooks or PC Tablets. A notebook computer is similar to a laptop computer and is generally smaller than a briefcase (up to 25% smaller than a laptop PC). A ‘Tablet’ is a type of notebook computer that has an LCD screen on which the user can write using a stylus. It is also a proprietary name for the Microsoft Windows operating system of the same name. Mention should be further made of ‘smart phones’ which are a combination of a cellular phone and a PDA. This type of hybrid device allows users to converse as well as perform tasks, such as accessing the Internet wirelessly and storing contacts information.

PDAs are universally smaller than either a notebook or tablet and have a processor and a combination of ROM (read only memory) and RAM (read access memory). Many use expansion cards, such as CompactFlash and SecureDigital (SD), to store applications and data.

Within the PDA market there are three main operating system manufacturers, each of whom have developed their own proprietary systems. Manufacturers are, consequently, left to position their products with operating systems from devices incorporating, among others, Palm OS^TM, Pocket PC^TM (replaces Windows CE^TM for most Windows based handhelds) or Blackberry^TM operating systems.

PDA ‘Types’

Two primary ‘types’ of PDAs are available on the market today:

1. Palmtop - type devices, such as the Palm m505, the Handspring Visor Pro and the Compaq iPaq. These devices are generally less that 5.3 inches tall, 3.2 inches wide and .7 inches deep and use one of two basic operating systems:
   • Palm OS - used on the Palm PDAs made by 3Com, Handspring, and Sony Clié.
   • Pocket PC (PPC) - Microsoft’s OS using a version of Windows CE^TM on Compaq iPaq, Hewlett-Packard Jornada, and Toshiba Pocket PC.
2. Handheld PCs (HPCs), such as the HP Jornada 720 and the NEC Mobile Pro 790. These devices include an integrated keyboard and a horizontal rather than vertical screen. HPCs use the Handheld PC 2000 operating system (and upwards from Microsoft based on the Pocket PC format for handheld PCs. Earlier models have used the Windows CE^TM operating system.

Functions Overview

Palm OS devices include basic tools for calendaring, contacts, lists and notes. Some of the devices also include connectivity software and e-mail capability. Third-party software for the Palm is a growing market—all types of software are available for the Palm from word processing to games. The Palm OS is easy to use for calendar, contacts and task functions. However, additional synchronization software must be installed to synch data with Outlook.

Pocket PCs and HPCs are Windows devices so the software is familiar to Office users. Pocket Word, Pocket Excel, Pocket Outlook and Internet Explorer have many of the same features of their PC versions. No additional software, other than an installation disk which usually comes with the device, is needed to synch with a desktop or laptop PC. These devices also easily handle synching to multiple machines—a valuable tool in moving data between office and home PCs. Pocket PCs and Handheld PCs have a range of software applications similar to those for Palm.

Battery Type and Battery Life

Most PDAs come with rechargeable lithium batteries. Palm-type devices require less energy so batteries typically last longer. Pocket and Handheld PCs, with their color screens and resource intense applications, drain batteries much faster. Lithium batteries last from a week to a month with intermittent use. They recharge easily in a couple of hours by placing them in their synch cradle or plugging them in with a charging cable. Some of the lower-end Palm-type devices use AAA batteries. Battery life can be as long as a couple of months but if a PDA has not been synched recently and batteries are not charged, there is the risk of losing data.

Connectivity

There are two main types of connectivity available for PDA users:

Land-line Connections

Handheld PCs have generally come with a built-in modem - just plug in a phone cord and dial. For other devices such as Palms and Pocket PCs, modems should be bought separately to connect to the internet or a corporate network over the phone. A user can purchase modems as CompactFlash cards and other PC cards, depending on the expansion slots available on a given device. Ethernet cards are also available to connect directly to your corporate network.

Wireless Connections

Wireless Modems
Wireless solutions are available in the form of wireless modems such as the PocketSpider and the Minstrel. Both of these modems use a CDPD (Cellular Digital Packet Data) network and require a subscription service to use but offer complete freedom from land-based phone lines in their service areas.

Bluetooth and Wi-Fi
One of the new technologies available for wireless connectivity is called Bluetooth. Any Bluetooth-enabled device, including phones, PDAs, printers and computers can exchange data (up to 1 Mbps) with any other Bluetooth device within its range (up to 300 ft). Bluetooth adapters can be added to Palm devices and Bluetooth cards to Pocket and Handheld PCs. For greater speed, 802.11b Ethernet networks, referred to as Wi-Fi, can facilitate data transfer even further. These wireless networks transfer data at 11 Mbps up to 500 ft. 802.11a Ethernet networks work at 54 Mbps and cover a range of 1000 ft but currently many enabled PDA card slots cannot handle data at that speed.

Mobile Phone Connections
Another way to connect to the Internet without a land-based phone line is through a cable or Bluetooth connection to a mobile phone. If a user is planning to connect with a cable, the mobile phone must have Internet capability and a cable designed to connect with a PDA. Not all combinations exist, so it is advisable to check with a specialist resource site (see PDA Resources) or a mobile phone vendor to verify that the two can connect.

Also see:
Web Delivery for PDAs
Wireless Networks
SMS and MMS
Multimedia Content Delivery
Trends
Accessibility
PDA Resources
Glossary