Windows CE and Pocket PC: FAQ

Windows CE 3.0

Microsoft Corporation

Updated April 2001

Common misconceptions about Microsoft® Windows® CE and Microsoft® Pocket PC circulate in online forums, such as Pocket PC newsgroups and e-mail messages. The answers to the following questions will help you make important distinctions between these products and allow you to dispel, rather than foster, misconceptions that you encounter.

What is Pocket PC?

Pocket PC is software for personal digital assistants (PDAs). Pocket PC has both operating system (OS) and application components bundled specifically for PDAs. These include a set of system components from the Windows CE OS and application components, such as Microsoft® Pocket Internet Explorer, Microsoft® Pocket Word, Microsoft® Pocket Excel, and Microsoft® Pocket Outlook. The Compaq iPAQ H3650 and the Hewlett-Packard Jornada 548 are examples of PDAs that run Pocket PC software.

What is Windows CE?

Windows CE is a set of components that an OS developer uses to build a proprietary OS. Original equipment manufacturers (OEMs) who purchase Windows CE use Platform Builder, an integrated development environment, to assemble and compile an OS image. The image includes Windows CE and custom components, and custom device drivers. The OS image is then programmed into the read-only memory of a microprocessor chipset.
Windows CE is not restricted to Pocket PC devices. It is appropriate for cash registers, cellular telephones, medical instruments, and any other appliance that requires a small, embedded OS.

Is the Pocket PC OS the same as Windows CE?

No. The Pocket PC OS is a custom version of Windows CE developed by Microsoft. It contains APIs and applications that are not included in Windows CE 3.0 itself. Likewise, Windows CE contains components that are not included in the Pocket PC OS.
Pocket PC devices do not all use the same Pocket PC OS, either. OEMs who build these devices make custom versions of the Pocket PC OS to add features specific to their devices. Thus, a Pocket PC device from one OEM might include different applications or device drivers than a Pocket PC from another OEM.

What are some differences between the Windows CE 3.0 OS and the Pocket PC OS?

The Pocket PC OS includes an optimized kernel, which allows the OS to operate with great efficiency. In addition, the Pocket PC OS supports ActiveSync 3.1. In contrast, Windows CE 3.0 includes Distributed Component Object Model (DCOM), which is not included in the Pocket PC OS, and supports ActiveSync 3.0.

What is the difference between a Pocket PC and a Palm-size PC?

Like the Pocket PC, Palm-size PC is also hardware and software. The OSs for these device families are based on different versions of Windows CE. The Palm-sized PC is based on Windows CE version 2.11 and the Pocket PC is based on Windows CE 3.0. Palm-sized PCs include the Compaq Aero. The Pocket PC OS takes advantage of more recent hardware improvements and incorporates improvements in Windows CE itself.

Can I upgrade the OS on a Pocket PC?

Yes, in some cases. Consult the OEM for your device about the availability of OS upgrades. Microsoft does not supply them. You may learn that your device cannot support newer versions of the OS if that OS was modified for newer hardware.
For example, the Compaq iPAQ and the Compaq Aero have different hardware features. The iPAQ, which is newer and smaller, has a better display, higher sound quality, and longer battery life. An OS upgrade for the Aero would not enhance these features. In short, installing the Pocket PC OS on your Compaq Aero would not turn it into an iPAQ.

Can I use Platform Builder to build a new OS and then flash the microprocessor chip myself?

No. As noted earlier, the Pocket PC OS is based on Windows CE, but includes additional components that are not available in Platform Builder. If you flash the chip in your device, you lose all of those extra components and you will not be able to reproduce them in Platform Builder.

Can I write applications for a Pocket PC?

You can use Microsoft® eMbedded Visual Tools 3.0, which includes software development kits (SDKs) for the Palm-sized PC and the Pocket PC. It includes all the tools you need to design, compile, link, debug, and install a Pocket PC application. As noted earlier, Platform Builder is a tool for developing custom operating systems, not for developing applications.

For More Information

For information about Pocket PCs, see the Microsoft Mobile Devices Web site. For information about Windows Embedded products, including Windows CE and Platform Builder, see the MSDN Windows Embedded Development Center and the Microsoft Windows Embedded Web site.