Psion Series 5

The Psion Series 5, developed by Psion PLC, a British company headquartered in London, England, was a groundbreaking personal digital assistant (PDA) released in 1998. It featured a unique sliding clamshell design, a 640x240 greyscale touchscreen, and a full QWERTY keyboard, making it highly functional for mobile productivity. Powered by a 32-bit ARM710T processor running at 18MHz, it supported CompactFlash storage, infrared connectivity, and ran EPOC32, an early version of what later became Symbian OS. The Series 5 was praised for its long battery life, typically lasting 10–20 hours on two AA batteries, and its robust software suite, including word processing, spreadsheets, and database management. The Series 5 was later succeeded by the Series 5mx in 1999, which featured a faster processor and improved display.