Understanding How PDAs Function

The primary role of a personal digital assistant (PDA) is to function as a portable electronic organizer or planner that is user-friendly and capable of syncing with your PC. It complements your PC rather than replacing it.

PDAs, also known as handheld devices or palmtop computers, have come a long way. Initially used to organize personal data like contacts, schedules, and tasks, modern devices also connect to the internet, function as GPS units, and support multimedia applications. Additionally, manufacturers have integrated PDAs with cell phones, media players, and other advanced electronic features.

As PDAs evolve, their capabilities continue to expand. This article explores the history of the PDA, its convergence with other devices, and the future direction it’s headed. We'll also discuss how PDAs operate and offer advice on how to choose the right one for your needs.

The Origin of the PDA

The earliest models of PDAs include the Psion Organiser and the Sharp Wizard, which were released in the mid- to late 1980s. Designed as portable computing devices, these early models featured small keyboards, a compact display, and basic functionalities like an alarm, calendar, phone pad, and calculator. They also supported specialized software like games and spreadsheets. The Psion Organiser II, launched in 1986, became particularly popular, selling over half a million units.

In 1993, Apple introduced the Newton MessagePad, priced at $700. This device offered users an electronic notepad, to-do list, calendar, phone log, and address book. Several features from the Newton, including the pressure-sensitive display with a stylus, handwriting recognition, an infrared port, and an expansion slot, became standard in PDAs. However, the Newton's size, cost, and complicated design, along with poor handwriting recognition, led to its discontinuation in 1998.

The PalmPilot debuted in March 1996, created by Palm Computing (then owned by U.S. Robotics). Priced under $300, it ran on its proprietary Palm operating system, was small enough to fit in a shirt pocket, and synced with users' PCs. The PalmPilot offered long battery life with AAA batteries, was simple to use, and could store thousands of contacts, appointments, and notes. Its compact design was partly due to the absence of a keyboard, with users inputting data using a stylus and the Graffiti language.

Microsoft was also making strides in portable computing, developing solutions like PenWindows and tablet PCs. In November 1996, they introduced Windows CE, their first operating system designed for mobile devices. Several companies, including HP, Compaq, and Casio, adopted it for their Handheld PCs, the first Windows-based rivals to the PalmPilot.

In the next section, we will explore the different types of PDAs available today.

Different PDA Types

Classic PDAs

Today’s traditional PDAs are descendants of the original PalmPilot and Microsoft Handheld PC devices. Palm devices run the Palm OS (operating system), while Microsoft Pocket PCs use Windows Mobile. The distinctions between the two operating systems have become less pronounced over time.

Palm PDAs

The majority of Palm devices are manufactured by palmOne, which offers the Zire and Tungsten product lines. The company was formed in 2003 after Palm Computing acquired Handspring, Inc. Sony, which once produced the Palm-based CLIE, ceased making PDAs in 2005.

Palm OS PDAs are celebrated for their simplicity. Key features include:

Pocket PCs

Pocket PC is the umbrella term for PDAs running Windows Mobile. Some of their key features include:

Smartphones

A smartphone is essentially a cell phone with PDA features, or a traditional PDA that includes cell phone capabilities, depending on its design and the manufacturer. These devices typically have the following characteristics:

It doesn’t resemble a PDA...

Other related devices include ultraportable computers, smart watches, and multimedia players. Ultraportable computers weigh anywhere from under a pound to about three pounds, feature a full desktop operating system (such as Windows XP), and typically include a small keyboard. Smart watches provide PDA-like functionality in a wristwatch format. For example, Microsoft’s SPOT (Smart Personal Objects Technology)-based watches can display MSN Direct information such as weather updates and news, along with calendar events and personal messages. Some multimedia players combine PDA capabilities with features like a digital camera, an MP3 player, and a video player.

In the upcoming section, we will explore the functions of PDAs and how they perform these tasks.

PDA Features

Even the most basic PDAs manage core personal information tasks, run applications, and sync seamlessly with PCs. Here’s a closer look at these essential features.

Manage Core PIM Functions

All PDAs are equipped with personal information management (PIM) software designed to assist with the following tasks to stay organized:

Run Software Applications

PDAs are capable of running various specialized software applications, including:

Synchronize with Computers

Since PDAs are designed to work alongside your PC, synchronization between the two is essential. For instance, if you create an appointment on your desktop computer, it should sync to your PDA. Similarly, any phone numbers you input on your PDA should be uploaded to your computer when needed.

Synchronization software on PDAs works alongside companion software installed on your PC. Microsoft Pocket PC devices utilize ActiveSync, while Palm OS devices employ HotSync synchronization software. On your computer, an application such as Microsoft Outlook or Palm Desktop is necessary to manage PIM data on the PC side.

The advantage of synchronization is that it ensures you always have a backup copy of your data, which can be a lifesaver if your PDA is damaged, lost, or runs out of battery power.

Common PDA Functions

Today, most PDAs come equipped with various wireless and multimedia functions. Here are some features commonly found across many, though not all, devices:

Fancy Features

Fancy Features

Premium PDAs offer advanced multimedia, security, and additional features that are typically absent from budget models:

Next, we will explore the computer that powers the PDA.

The PDA's Computer

Microprocessors and Memory

Like traditional desktop and laptop computers, PDAs are powered by microprocessors. These microprocessors act as the brain of the PDA, managing all tasks based on programmed instructions. Unlike their desktop and laptop counterparts, PDAs use smaller, more cost-effective microprocessors. While these tend to be slower than those found in desktop PCs and laptops, they are still sufficient for the tasks that PDAs perform. The advantages of being compact and affordable outweigh the drawback of slower processing speeds.

PDAs do not contain a hard disk. Instead, they store essential programs (such as the address book, calendar, memo pad, and operating system) in a read-only memory (ROM) chip, which remains intact even when the device is powered off. Your personal data and any additional programs are stored in the device's random-access memory (RAM), which is only accessible when the device is on. Thanks to their design, PDAs protect the data in RAM by drawing a small amount of power from the battery, even when the device is turned off.

Lower-end PDAs come with less RAM, but as most applications take up significant memory, most models are equipped with larger memory capacities. Pocket PC devices, in particular, typically require more resources and come with even more RAM. To expand memory further, many PDAs allow for the use of removable flash media cards, which are useful for storing large files or multimedia content like digital photos.

Some newer models of PDAs, like the Palm Tungsten E2, utilize flash memory instead of RAM. Flash memory is non-volatile, meaning it retains stored data and applications even when the device runs out of battery power.

Operating Systems

The operating system is responsible for providing the pre-programmed instructions that guide the microprocessor's actions. PDAs use simpler operating systems compared to those on PCs. These systems contain fewer instructions, which require less memory to run.

PDAs and smartphones generally run one of two operating systems: Palm OS or Windows Mobile. However, RIM has developed a dedicated OS for its BlackBerry devices, and the Symbian OS powers certain smartphones as well.

In the following section, we will explore the other components that make up a PDA.

PDA Battery

We've already covered the PDA's microprocessor, memory, and operating system. Now let's dive into the remaining components of the PDA.

Batteries

PDAs are powered by batteries. Some models rely on disposable alkaline (AAA) batteries, while others use rechargeable options like lithium, nickel-cadmium, or nickel-metal hydride. Battery life varies depending on the type of PDA and its usage. Below are some factors that can drain your PDA's battery:

Battery life can range from a few hours to several months, depending on the specific PDA model and its features. Most PDAs are equipped with power management systems designed to prolong battery life. Even when the battery gets so low that the device won't turn on (but it will give you plenty of notice), there is typically enough power left to maintain the RAM's memory.

If the batteries are completely drained or removed, many PDAs are equipped with an internal backup battery that provides temporary power (usually for around 30 minutes or less) until you can replace the batteries. Without any power, the data in the RAM will be lost, which is why it's essential to regularly back up or synchronize your PDA.

Along with battery power, many PDAs are supplied with AC adapters to allow them to run off a standard electrical outlet. A car adapter is also typically available as an optional accessory.

LCD Display

PDAs feature an LCD (liquid-crystal display) screen. Unlike the LCD screens on desktop or laptop computers, which are used exclusively for output, PDAs use their screens for both input and output. While the LCD screens of PDAs are smaller than those of laptops, their size can vary. Nearly all PDAs now come with color displays.

The displays on PDAs typically offer the following features:

Input Methods

PDAs offer different methods for inputting data and commands. Some devices rely solely on a stylus and touchscreen, along with a handwriting recognition program. By using a plastic stylus, you write characters directly onto the PDA's screen or a specific writing area. The software inside the PDA then converts your drawn characters into letters and numbers. On Palm devices, the handwriting recognition software is known as Graffiti. Graffiti requires you to follow a specific style for each letter, with a unique alphabet. For example, the letter "A" is written as an upside-down V, while "F" resembles an inverted L. To improve recognition accuracy, Graffiti requires you to draw letters in one area of the screen and numbers in another.

Pocket PC PDAs provide three handwriting recognition options: Transcriber, Letter Recognizer, and Block Recognizer. Letter Recognizer and Block Recognizer are similar to Graffiti, requiring special alphabetic forms. In contrast, Transcriber allows you to write in your usual handwriting, as long as it is legible. This function is comparable to the handwriting recognition found on Tablet PCs.

If you're struggling with PDA handwriting input, you can switch to a miniature on-screen keyboard. It mimics a regular keyboard, but you tap on the keys with the stylus. Many devices also feature a small, often cramped QWERTY keyboard, which usually requires you to use your thumbs. Additionally, you can connect a full-sized keyboard to the PDA using Bluetooth or a USB port. Each device typically has a few buttons and navigation dials that help you open applications and scroll through your files.

PDA Display and Input

LCD Display

PDAs are equipped with an LCD (liquid-crystal display) screen. Unlike the LCDs used in desktop or laptop computers, which serve purely as output devices, PDAs use their screens for both input and output. The LCD screens on PDAs are smaller than those on laptops, though they come in varying sizes. Nearly all PDAs today feature color displays.

PDA screens feature the following characteristics:

Input Methods

PDAs differ in the way data and commands are input. Some models rely exclusively on a stylus and touchscreen, combined with handwriting recognition software. The stylus is used to trace characters on the PDA’s display or designated writing space. The device’s internal software then converts these drawn shapes into letters and numbers. For Palm devices, this software is called Graffiti, which requires each letter to be written in a specific style using a specialized alphabet. For example, the letter "A" is drawn as an inverted V, and the letter "F" resembles an upside-down L. To help Graffiti make more accurate translations, you must write letters in one part of the screen and numbers in another.

Pocket PC PDAs come with three handwriting-recognition apps: Transcriber, Letter Recognizer, and Block Recognizer. Both Letter Recognizer and Block Recognizer are similar to Graffiti, requiring unique alphabets for input. In contrast, Transcriber is capable of recognizing regular handwriting, as long as it is legible. This feature is similar to the handwriting recognition found in Tablet PCs.

If you're struggling with handwriting input on your PDA, you can opt for a compact on-screen keyboard that mimics a standard keyboard. Instead of pressing physical keys, you'll tap on the letters using the stylus. Many devices also offer a small (and often cramped) QWERTY keyboard, with some requiring thumb typing. Additionally, you can connect a full-sized keyboard to your PDA through Bluetooth or a USB port. Each model typically features buttons and navigation dials for accessing applications and scrolling through files.

Buying a PDA

When you're considering purchasing a PDA, the most important question to ask yourself is, "What will be my primary use for this device?" If you just need basic PIM (Personal Information Management) functions and organization, wireless connectivity might not be necessary. However, if you're a frequent traveler and want to stay connected via email, having Wi-Fi capability or opting for a smartphone with cellular data will be essential.

Since many people use PDAs as accessories for their PCs, synchronization becomes a key factor. Look for a model that easily syncs with the PIM software you use on your computer. For instance, if you're a Macintosh user or don't rely on Microsoft Outlook, a Palm OS device may be a better fit for you.

The method by which you enter data into your device is also a crucial factor. If you're planning to use your PDA for tasks like emailing or other text-heavy applications, consider one that includes a built-in keyboard. If possible, test out the keyboard before making your purchase to ensure it fits your needs.

The dimensions and design of the device, including its display, play a significant role in your decision. The device should feel comfortable in your hand, and the display should be large enough and clear enough to meet your needs. As with the keyboard, it's a good idea to visit a store that carries the devices you're interested in so that you can test them out before making a purchase.

If you're looking for an all-in-one device that incorporates features such as GPS, an MP3 player, or a digital camera, make sure to find a device that comes with these functions built in. Alternatively, choose a device that includes an SDIO slot, allowing you to use compatible SDIO accessories. If you plan on using several applications or need extra storage for large files, look for a device that supports flash memory media cards.

When considering accessories, think about additional items such as a spare battery, a car or travel charger, headphones, a carrying case, a screen protector, and extra keyboards.

For those interested in a smartphone, many of the same factors for buying a cell phone should be considered. Key points to check include the coverage area of service providers, any extra costs for cellular data service, and the length of the service contract. For more details, see How Buying a Cell Phone Works. Additionally, consider the various smartphone operating systems available, such as Symbian, BlackBerry, Palm OS, and Windows Mobile Pocket PC Phone edition.

The Future of PDAs

Traditional PDAs have seen a decline in popularity compared to previous years. Some major manufacturers, including Sony and Toshiba, have exited the PDA market. According to the IDC Worldwide Handheld QView press release dated February 2, 2005, the sales of traditional PDAs have experienced a significant drop in recent years.

To remain relevant in the future, PDAs must continue to build upon their core Personal Information Management (PIM) functions. The growing popularity of smartphones and devices that integrate additional features such as wireless Internet, GPS, and multimedia capabilities highlights the need for PDAs to evolve.

For more information and answers to commonly asked questions about PDAs, refer to the FAQ on the following page.

PDA FAQ

Below are some frequently asked questions about PDAs with their answers.

Why might I need a PDA?

A PDA could be useful in the following situations:

What is the price range for PDAs?

The cost of PDAs ranges from approximately $150 to $1,000, depending on the features you select. Typically, most PDAs fall within the $300 to $500 price range.

Is it possible for my PDA to sync with my desktop or laptop?

PDAs are designed to interface with desktops or laptops, allowing you to make the data on your larger computer portable. Keeping this information synchronized is key, and PDAs have built-in features to facilitate this. This process, known as data synchronization or syncing, typically occurs through a serial or USB port on the PDA. Some models use a cradle to dock the PDA while it's connected to your PC. Many PDAs also come equipped with an infrared communication port that uses infrared light to transmit data between a PDA and a PC, or between two PDAs. For more advanced models, wireless methods can be used to sync data with a PC or a network via wireless e-mail/Internet services, much like those found in newer smartphones. Some PDAs even support telephone modem accessories for transferring files between the PDA and a PC or network.

Which PDA operating system should I choose?

Each operating system offers unique benefits. Palm OS, the market leader, has a large selection of software, both available and in development. However, developers are also focusing on software for PocketPC. Palm OS is known for using less memory and running faster, with users reporting it as easier to navigate. On the other hand, PocketPC supports color displays, graphics, standard Windows applications like Word and Excel, and other devices such as built-in MP3 or MPEG movie players. However, it tends to use more memory and runs slower, with users mentioning that it is more complex to use.

Additional Common PDA Queries

If my PDA is stolen, which could happen given its compact size, what steps can I take to secure my personal data?

By syncing your PDA with your desktop computer, you ensure that a backup of your data is always available. So if your PDA is lost, your data will still be preserved. Additionally, you can protect your PDA's information by setting up password protection. Security software is also available to prevent unauthorized access, and encryption features are included in some applications for added security.

How does a PDA interact with the Internet?

To improve Internet functionality on their devices, PDA manufacturers have implemented a technique known as Web Clipping. Rather than downloading entire web pages, Web Clipping extracts specific pieces of text and sends them wirelessly to your PDA. Information like news headlines, phone numbers, and emails can be delivered this way.

Is it possible for handheld computers to get viruses?

Viruses have affected certain PDA models. For example, the Phage virus can overwrite executable files on some Palm devices. Several companies now offer antivirus software designed specifically for PDAs. Downloading programs from the internet can expose your device to viruses, so be cautious about downloading files or programs from unknown sources. For more information about computer viruses, refer to How Computer Viruses Work.

How long will it take before a PDA runs out of memory?

The typical data stored on PDAs, such as text without images, doesn't consume much memory, allowing you to store a substantial amount. Some PDAs require additional memory for their operating systems, and if you use your device for email or web browsing, you'll need more memory. If you're concerned about space, you can opt for a model with expandable memory.

If I purchase a PDA today, how soon will it become outdated?

Like other areas of computing, PDA technology evolves rapidly. Today's models offer more features at lower prices than those from just a few years ago. In the future, PDAs are expected to integrate with cell phones, allowing them to communicate through cellular networks for both voice and text. As computer technology progresses, PDAs will likely become faster and offer more memory. When choosing a PDA, it's important to focus on how you'll use it. For instance, if your main goal is to have an organizer for appointments and contacts, a reliable PDA will serve you well for years. However, if you're someone who gets excited about the latest tech, you might want to consider a model that allows upgrades and keep an eye on new software releases.

On the following page, you'll discover PDA software programs that can help make your tasks simpler and more efficient.

PDA Software

Most PDAs come with a sync tool that ensures your data is synchronized and updated between both your computer and your PDA. For instance, Microsoft Pocket PCs use ActiveSync, Palm OS devices rely on HotSync, and BlackBerry has Desktop Software.

The process for downloading and installing software on PDAs is quite similar across all models:

PDAs have always been vital tools for busy executives. The software available for today's PDAs helps professionals stay organized and connected, allowing them to work from virtually anywhere.

Most PDAs come pre-installed with an office suite (such as word processing, spreadsheets, etc.), a web browser, and an email client. This enables traveling professionals to view email attachments, edit documents, and send them back to colleagues while on the move.

With the majority of PDAs now offering internet access, their software applications allow users to connect to real-time online data.

Various professionals who benefit from using PDA software applications include:

[Sources: Handango, Sage Software, CollectiveMed, and Orbitron Technologies]

However, PDAs are not solely for business purposes. The same software also enables users to download and enjoy games such as chess, Sudoku, and backgammon.

PDA software also exists that lets you record DVDs for viewing on your handheld device, and other applications can turn your PDA into a portable photo gallery, MP3 player, or eBook reader.

Whether you're using your PDA for work or fun, keep in mind that there's software running behind the scenes to make everything possible.