EPOC

EPOC was a mobile operating system developed by Psion for personal digital assistants (PDAs) and later adapted for early smartphones. Introduced in the 1990s, EPOC provided a multitasking, real-time kernel designed to run on compact, low-power hardware. The platform offered a modular set of system libraries and a native application environment, and it served as the foundation that would evolve into Symbian OS.

Versions and evolution: The 32-bit evolution, often referred to as EPOC32, targeted devices with greater memory and processing power, such as Psion’s Series 5 line. In the late 1990s, Psion formed a joint venture with Nokia and Ericsson to create Symbian Ltd to license and further develop the OS. During this transition, the branding shifted toward Symbian OS, and EPOC32 became part of the historical lineage leading to the Symbian platform used on many smartphones in the 2000s.

Architecture and development: EPOC featured a modular architecture with a real-time kernel and a client-server style of operation, designed to run on ARM-based hardware common in mobile devices of the era. Development tools and APIs evolved into the Symbian C++ APIs, which became the standard for applications on subsequent versions of the platform.

Impact and legacy: EPOC’s evolution into Symbian OS helped establish one of the first widely deployed mobile operating systems, powering a broad ecosystem of devices and applications in the 2000s. Symbian OS remained significant until it was gradually supplanted by iOS and Android in the following decade. The EPOC lineage thus played a key role in shaping early mobile software ecosystems.