Overview of Windows Mobile
Windows CE, Pocket PC, and Windows Mobile
In the past few years Microsoft has used a number of terms for the version of Windows used for mobile devices.
In 2000, Microsoft introduced the Pocket PC, which used Windows CE 3.0 as the underlying operating system together with a graphical user interface, and additional applications such as Pocket Word. Although technically these devices were running Windows CE, they were branded and referred to as Pocket PCs. Consequently, many users were unaware that Pocket PC devices used Windows CE as the underlying operating system.
In 2003, Microsoft released a new version of Pocket PC, with Windows CE 4.2 as the underlying operating system. However, in order to create a stronger branding, Microsoft started referring to these new Pocket PC devices as Windows Mobile devices. Three different variations of Windows Mobile were released, each targeted at a different type of mobile device:
- Windows Mobile for Pocket PC—for Pocket PC devices.
- Windows Mobile for Pocket PC Phone Edition—for Pocket PC devices with an integrated phone.
- Windows Mobile for Smartphone—for “smartphones”, or phones without a touch screen, running Windows Mobile.
In 2004, Microsoft released another update, Windows Mobile 2003 Second Edition, and had subsequently dropped the use of the term “Pocket PC”.
In 2005, Microsoft released Windows Mobile 5, which was built using the Windows CE 5.1 development platform.
In 2007, Microsoft released Windows Mobile 6, which is built using the Windows CE 5.2 development platform. The three variations of Windows Mobile, introduced in 2003, were renamed to the following:
- Windows Mobile for Pocket PC has been renamed to Windows Mobile Classic.
- Windows Mobile for Pocket PC Phone Edition has been renamed to Windows Mobile Professional.
- Windows Mobile for Smartphone has been renamed to Windows Mobile Standard.
With ArcPad 5 and ArcPad 6, for ease of communication ESRI used the term “Windows CE” as a generic term to include both Windows CE and Pocket PC devices. For the first few years this approach worked as there were very few Pocket PC devices on the market—and most rugged mobile devices used Windows CE. Today, the situation has reversed with most devices running Windows Mobile and very few devices running pure Windows CE. Consequently, at ArcPad 7, ESRI used the term “Windows Mobile” as a generic term to include both Windows Mobile and Windows CE devices.
In ArcPad 8.0 and above, only Windows Mobile 5 and above is supported. So when the term Windows Mobile is used, it refers to Windows Mobile 5 and above.
If you are familiar with desktop Windows, you should immediately recognize and be able to use the Windows Mobile user interface.
The similar file system for desktop Windows (Windows 7, Vista and XP ) and Windows Mobile means that no conversion takes place when copying or moving files between desktop PCs and Windows Mobile devices. The only exception is when the communication software, Microsoft ActiveSync® or Windows Mobile Device Center, is specifically configured to convert files to formats used by Windows Mobile applications such as Pocket Word.
ArcPad takes advantage of the similar file systems when sharing GIS data with desktop GIS software. GIS files which are supported by ArcPad, such as shapefiles and supported images, can be used with desktop GIS software, such as ArcView, and then copied to the Windows Mobile device for use with ArcPad—no file conversion is required at any point. Although the file systems are similar, the medium for storing files is quite different and constitutes one of the main differences, from a user’s perspective, between Windows Mobile and desktop Windows.
File storage and program memory
Windows Mobile devices do not use hard drives for storage like desktop PCs—except when a Compact Flash or PC Card hard drive is used as an accessory for additional storage. Instead, ROM, random access memory (RAM), and flash memory are used for storage. Just as on desktop PCs, RAM is volatile—meaning that the contents of RAM are lost when a Windows Mobile device is rebooted or shut down. Unlike desktop PCs, switching off a Windows Mobile device does not clear the contents of RAM since in the latter case only the screen is turned off and not the actual device.
The operating system is stored in ROM; it is not stored on the hard drive as in desktop PCs. Consequently, Windows Mobile devices boot up much more quickly than desktop PCs. Reading the operating system from ROM is much faster than reading the operating system from a hard disk.
With Windows Mobile 5 (and later) devices, RAM is only available for running the operating system and programs. Windows Mobile 5 (and later) devices include non-volatile flash memory, or built-in storage, for installing application programs and data.
The above example shows the memory usage of a Windows Mobile 5 device, which has 54.84 MB built-in storage and 64 MB of RAM—of which 47.09 MB is available for running programs.
Storage cards—either flash memory or hard drives—can increase the amount of storage space for a Windows Mobile device, but they cannot increase the amount of memory available for running programs. Programs can only run in the memory installed on the device. It is therefore important to limit the amount of data and programs stored in RAM (for older devices) and in so doing maximize the amount of free memory available for running programs. Fortunately, an increasing number of Windows Mobile devices include built-in, nonvolatile, flash memory—in addition to ROM and RAM. For these devices it is recommended that applications, and optionally data, be installed in the built-in storage—keeping most of the RAM free for running the operating system and programs. Different Windows Mobile devices use different names for the built-in storage: Dell uses the name Built-in Storage, HP uses the name iPAQ File Store, Thales uses the name MyDevice, and Trimble uses the name Disk.
To view memory on a Windows Mobile device, tap Start>Settings>Control Panel, then double-tap the System icon to open the System Properties dialog box. Tap the Memory tab to open the Memory settings page.