| Developer | Psion |
|---|---|
| Written in | Assembly, C (EPOC16) C++ (EPOC32) |
| OS family | EPOC |
| Working state | Discontinued, succeeded by Symbian |
| Source model | Closed source |
| Initial release | 1989 |
| Latest release | ER5u / 2000 |
| Marketing target | PDAs, mobile phones |
| Available in | English |
| Platforms | x86 via NEC V30H (EPOC16) ARM (EPOC32) |
| Kernel type | Microkernel |
| Default user interface | Eikon et al. |
| License | Proprietary |
| Succeeded by | Symbian |
| Support status | |
| Unsupported | |
EPOC is a mobile operating system developed by Psion, a British company founded in 1980. It began as a 16-bit operating system (OS) for Psion's own x86-compatible devices, and was later replaced by a 32-bit system for x86 and ARM. Psion licensed the 32-bit system to other hardware makers, such as Ericsson.
To distinguish it from the 16-bit OS, the 32-bit version was sometimes called EPOC32. Technologically, it was a major departure from the 16-bit version (which came to be called EPOC16 or SIBO). In 1998, the 32-bit version was renamed Symbian OS. After Nokia acquired the rights to Symbian in 2010, they published Symbian's source code under the Eclipse Public License. In 2011, Nokia rescinded the open-source license for subsequent releases of the software.[1]