A Pocket PC, abbreviated P/PC or PPC, is a hardware specification for a handheld-sized computer (Personal digital assistant) that runs the Microsoft Windows Mobile operating system. It may have the capability to run an alternative operating system like NetBSD, Linux, Android or others. It has many of the capabilities of modern desktop PCs.
Currently there are thousands of applications for handhelds adhering to the Microsoft Pocket PC specification, many of which are freeware. Some of these devices also include mobile phone features. Microsoft compliant Pocket PCs can also be used with many other add-ons like GPS receivers, barcode readers, RFID readers, and cameras.
In 2007, with the advent of Windows Mobile 6, Microsoft dropped the name Pocket PC in favor of a new naming scheme. Devices without an integrated phone are called Windows Mobile Classic devices instead of Pocket PCs. Devices with an integrated phone and a touch screen are called Windows Mobile Professional devices and devices without a touch screen are called Windows Mobile Standard devices.
From a technical standpoint, "Pocket PC" is a Microsoft specification that sets various hardware and software requirements for mobile devices bearing the "Pocket PC" label.
For instance, any device which is to be classified as a Pocket PC must:
Pocket PCs running previous versions of the operating system generally stored user-installed applications and data in RAM, which meant that if the battery was depleted the device would lose all of its data. Windows Mobile 5.0 solved this problem by storing all user data in persistent (flash) memory, leaving the RAM to be used only for running applications, as it would be on a desktop computer. As a result, Windows Mobile 5.0 Pocket PCs generally had a greater amount of flash memory, and a smaller amount of RAM, compared to earlier devices
Windows Mobile 2003 Second Edition added native landscape, square screen and VGA support as well as other fixes and changes to those features already present in the original release of Windows Mobile 2003.
Before the Pocket PC brand was launched, there were other Windows-based machines of the same form factor made by HP, Philips, and others called Palm-size PCs. These devices ran Windows CE 2.0–2.11 and had an interface that was similar to the then-current desktop versions of Windows, such as Windows 98.
Companies like O2, T-Mobile and Orange are marketing Pocket PCs that have integrated mobile telephony (smartphones). All users have to do is put in the SIM card and follow the wizard, to put their SIM contacts in the address book. An example is O2's Xda, or T-Mobile's MDA Compact. Both of these devices, whilst bearing the phone operator's logo, are actually manufactured by the dominant Pocket PC manufacturer HTC.
One of the more popular high-end consumer-market Pocket PCs was the Dell Axim x51v, which was discontinued in 2007. Hardware specs included 3.7" color TFT VGA display with 640x480 resolution, Intel XScaleTM PXA270 Processor at 624 MHz, 336MB of Memory (256MB Flash, 64MB SDRAM), integrated 802.11b and Bluetooth 1.2, integrated Intel 2700G multimedia accelerator with 16MB video memory. Expansion was possible via CompactFlash Type II and SD slots (supporting SDIO Now!, SDIO and MMC cards). Included is a 1,100 mAh user replaceable battery (est. 4-6.5 hours, 2200mAh also available).
Some Pocket PCs feature integrated GPS often combined with mobile phone functionality. Pocket PCs with built-in telephony differ from Windows Mobile Smartphone Edition devices in several respects, including the lack of a touchscreen on the latter. Some examples of current Pocket PCs with GPS integrated are the Fujitsu Siemens Pocket Loox N560, a high-end Pocket PC with a VGA screen and an integrated SiRF Star III GPS; the HTC TyTN, a small communicator with integrated slide in keyboard; the HP hw6945 and HP iPAQ hw6515 with integrated thumb-board, GPS and GSM/GPRS telephony; the HTC top of the line Universal, branded as the QTek 9000 (also branded by various telecommunications companies as the Orange SPV M5000, T-mobile MDA Pro, Vodafone VPA IV, O2 Xda Exec, i-Mate JasJar, Dopod 900).
A newer entrant into the Pocket PC market is Palm which sells devices like the Treo 700w/wx based on Windows Mobile 5.0 and featuring integrated telephony. Previously Palm only produced PDAs running the Palm OS (as did the first versions of the Palm Treo) and still sell versions of the Treo based on the Palm operating system.
HTC, responsible for manufacturing up to 80% of all phone enabled Windows Mobile devices for other companies (including HP and O2) as well as many non-phone enabled Pocket PCs (for companies such as Dell, HP and Fujitsu Siemens), are now marketing Windows Mobile devices under their own brand (such as the HTC Touch), as well as that of Dopod.