iPAQ presently refers to a Pocket PC and personal digital assistant first unveiled by Compaq in April 2000; the name was borrowed from Compaq's earlier iPAQ Desktop Personal Computers. Since Hewlett-Packard's acquisition of Compaq, the product has been marketed by HP. The device is the main competition to the Palm, but provides more multimedia capabilities using a Microsoft Windows interface. In addition to this, there are several Linux distributions that will also operate on some of these devices. Earlier, units were modular. "Sleeve" accessories, technically called jackets, which slide around the unit and add functionality such as a card reader, wireless networking, GPS, and even extra batteries were used. Current iPAQs have most of these features integrated into the base device itself.

Hewlett-Packard introduced the first SmartPhone iPaq Pocket PC that looks like a regular cell phone and has VoIP capability. The series is the HP iPAQ 500 Series Voice Messenger.HP Press release

History and development of iPAQ models

The iPaq was developed by Digital Equipment Corporation Western Research Laboratory (WRL), the internal code name for it was Itsy. The name was used by Compaq to continue their Compaq Aero handheld line. With the acquisition of Compaq by Hewlett-Packard, HP stopped producing their Jornada line of Microsoft Windows powered Pocket PCs and continued developing and marketing Pocket PCs in the iPAQ line.

In June 2003, HP retired the h3xxx line of iPAQs and introduced the h1xxx line of iPAQs targeted at price conscious buyers, the h2xxx consumer line, and the h5xxx line, targeted at business customers. They were sold pre-installed with the Windows Mobile for Pocket PC 2003 Operating System. The h63xx series of iPAQs running the Phone Edition of Windows Mobile 2003, the hx47xx series and the rz17xx series, both running the Second Edition of Windows Mobile 2003 were introduced in August 2004. In February 2005 the iPAQ Mobile Messenger hw6500 series was introduced to selected media at the 3GSM conference in Cannes, France.

In February 2007, HP announced the iPAQ rx4000 Mobile Media Companion devices to work as a PDA/media device and rx5000 Travel Companion series to work as PDA/GPS units. Both series of iPAQs work on the Windows Mobile 5 Operating System. In the same month, HP announced their first Windows Mobile 6 device, the iPAQ 500 Series Voice Messenger, with the Windows Mobile 6 Standard Operating System, and numeric pad. Currently, the only iPAQs being sold which run the Windows Mobile 5 Operating System are the hx2000 series, the rx5900 series and the hw6900 series.