If you have been researching hand-held units, you know there is lots of hype about the different platforms out there.  It may not be immediately apparent which one is best for your application.  We offer this analysis in the hope that it can clarify a few issues and help in your decision. 

Basis of discussion
This paper represents our opinion, based on years of experience with hand-held computers.  Experience with a specific make or model may be limited, but the wide variety of our experience highlights the important features to consider.  We are also looking at those factors that apply to data collectors.

A clear distinction must be made between consumer models and business/industrial hand-held hardware.  The same is true with applications.  Things that apply to the consumer/office arena do not necessarily apply to the business/industrial arena - and vice versa.

Currently, we primarily support the Palm, but we are moving to support both the PC and PocketPC/Windows Mobile platforms.  A version of PocketLog for PocketPC/Windows Mobile is currently under development.  We expect to port DataGet to the Windows Mobile platform utilizing the DataGetUSB line of adapters. Future plans include wireless/Bluetooth adapters and software.

General considerations for Data Collectors
There are a number of important general factors when implementing a data collector on a PDA (or Mobile Computer.  )

• Text entry - generally, you want to avoid requiring the entry of lots of text, as hand-helds have limited keyboards.  Use drop-down selector lists, checkboxes and similar devices instead.

• Simplify - hand-helds have limited screens and display capabilities, and it is very easy to get lost.  The software should make navigation easy and intuitive.   The design should be clear and straightforward.   Often it is harder to develop this kind of software, to achieve the proper balance between functionality and ease-of-use.  Simplify your requirements and make sure the software can meet them without a confusing workflow.

• Memory - most hand-helds today have more than enough memory to function as data collectors.  The issue is not how much memory do they have, but how much data do you risk losing if the battery dies or hand-held is damaged or lost.

• Interface - the hand-held must play well with the PC.  Transferring data should be simple and straightforward, and accomplished with the push of a button or a couple clicks of the mouse.

• Battery - most consumer hardware now has built-in rechargeable batteries.  These batteries may not be enough for extended data collection projects.  Most industrial units have replaceable, rechargeable battery packs - should your battery run down, you can quickly replace the battery and continue with your work.

• Screen - basically the choice is between color and black&white. Color units tend to drain the battery faster.  Black&white units can sometimes be a good choice as too many colors can be distracting.  B&W (or Grayscale) screens are often easier to see in bright sunlight.

• Accessories - industrial units often accommodate accessories like barcode readers that are not available for consumer PDAs.

• Rough handling - industrial units are built to withstand rough handling and adverse environments. While no hand-held hardware is indestructible, ruggedized industrial units will easily withstand treatment that would rapidly destroy consumer hardware.

• Standard OS - Many data collectors use a proprietary OS.  This limits you to the types of software you can use.  Further, if the vendor for your software goes out of business, finding an alternate can be difficult.  Standard OS's such as Palm and PocketPC let you expand the usage of your hardware, and help to insure that you can support for your software. Further, there are simply more applications available for the standard OS's.

About Palms
Palms were built from the ground up for the hand-held environment.  They quickly became overwhelmingly dominant and tens of thousands of software applications have been written for them.  There are probably more Palm PDAs in service than all other brands combined.  Palms tend to cost less than other brands.  Palm was designed from the start to be a stand-alone computer that interfaced well with the PC.  Software written for one level of the Palm OS tends to work well with subsequent versions.  The hardware can vary between versions and vendors, but affects primarily the interface connection.

For field data collection, two hardened units are popular - Meazura and Symbol.  We support the Meazura RDA and the Symbol SPT1550.  The ACCESS website features an overview of Palm hardware including the Meazura.

Input on a Palm is done using a touch-screen.  This makes the Palm very easy to use, but can be a detriment in some environments - the stylus can be easily lost, the unit can be difficult to use with gloves, and the screen is not as impact-resistant as non-touch screen devices. Color screens are not generally available on hardened units.  Battery life is very good on hardened units.

Hype and rumors about the supposed future demise of Palm apply to consumer and phone devices - not to business and industrial devices (PDAs).  The Palm OS is a stable, and mature, platform for business and industrial applications such as SPC or general data collection.  With over 20,000 software titles available, the Palm platform will be around for a long time.

ACCESS, the new owners of the Palm OS have an informative page detailing many of the benefits of the Palm OS - including a TCO comparison between Palm and Windows Mobile.  For more information, see their overview of the Palm OS.

About PocketPC/Windows Mobile
PocketPC/Windows Mobile was designed as subset of Windows/PC, and was intended to look and act as much like your PC as possible.  There have been several releases of Windows hand-helds, and software written for one version is not always compatible with other, newer or older, versions.  We are experiencing problems between Windows CE and Windows Mobile, and between different versions of each (specifically 5.0 and 6.0).

For field data collection, there are a number of brands available.   PocketLog, when released, will run on most brands, and DataGet will run on selected mobile hardware that supports a "USB Host" connection. 

Generally, the PocketPC form factor uses touch screens, and units with keyboards (often ABC, not QWERTY) use Windows Mobile.  Each vendor/manufacturer tends to customize their version of the OS, so software should be tested for full compatibility.  Keyboard units do allow easier text entry, but may not be easy to use with gloves. PocketPC/Windows Mobile use color screens which tends to shorten battery life.

PocketPC/Windows Mobile tends to be more expensive than Palm hardware - especially for ruggedized, field units, but can be the best choice in enterprises where already established, or where other software indicates their use.

Conclusion

• In a stand-alone environment, Palm gives the most 'bang for the buck'.  In an Enterprise situation, the PocketPC/Windows Mobile may be a better fit.

• Review carefully how you will be using your unit.  Consumer-oriented hardware may not stand up in industrial/field data collection, but may be preferable in an office or sales environment.

• Don't buy your hardware based on supposed future compatibility as either platform may die or change.  Your decision should be a business decision based on ROI.  Any hardware you buy now will likely be incompatible within a few years.  On the other hand, ruggedized units have long life and many DOS-based units are still around.  While they won't run the latest off-the-shelf software, they continue to perform the functions for which they were purchased.

• Industrial/ruggedized units have longer product lifetimes than do consumer units.  Consumer units tend to change each year, while industrial units tend to last five years or longer.  The Symbol 1500 series, for instance, has been available since 1998.

• If you operate in bright sunlight, grayscale (B&W) screens are superior to color screens.