Created: 10 September 2026 · Last edited: 22 October 2026

In December 1994, Sharp introduced a new type of personal digital assistant (PDA) under the name Zaurus ZR-5000. Rather than calling it an electronic organiser, Sharp coined the term K-PDA, short for Keyboard-enhanced Personal Digital Assistant. The new device combined a miniature QWERTY keyboard with pen-based input, bringing together two approaches to mobile computing in a single clamshell design.

The ZR-5000 is based on Sharp's earlier Wizard organisers, but takes the concept further with a graphical user interface, multitasking-style windows and support for additional software. It runs Synergy, Sharp's proprietary 16-bit operating system, and features a Sharp-designed 16-bit processor and 1 MB of RAM, of which approximately 750 KB is available for user data and add-on programs.

The ZR-5000 features a 4-inch DFSTN LCD touchscreen with a resolution of 320 × 240 pixels. The display is not backlit, so it relies on ambient light for visibility. The display's touchscreen supports handwritten notes, sketches, text selection and drag-and-drop operations using the supplied cordless stylus. Unlike handwriting-recognition systems, its ink-based notes are stored as objects rather than images, allowing them to be handled more efficiently. For longer texts, the miniature QWERTY keyboard offers a more conventional input method.

The built-in software includes tools for managing appointments and contacts, keeping notes, and creating documents. Its word processor can even automatically format letters by filling in details such as the recipient, date, opening and closing, and the sender's signature. A Type II PC Card slot allows the device to be expanded with compatible peripherals and memory cards, while serial and infrared interfaces provide ways to exchange data with other devices.

Although the ZR-5000 supports communications applications, it doesn't have a built-in modem. Instead, the optional CE-FM4 fax/modem provides data communications at up to 2,400 bps and fax transmission at 9,600 bps. Sharp also offers the ZR-5000FX, a bundle that includes this accessory.

The Zaurus ZR-5000 went on sale in the US in January 1995 for a suggested retail price of US$749. The ZR-5000FX bundle cost US$849.