ATI Nucleus PLUS

Nucleus PLUS is a real-time operating system (RTOS) developed by ATI in 1993. Many early Samsung and LG feature phones used proprietary operating systems based on Nucleus PLUS.

MediaTek's proprietary OS is based on Nucleus RTOS as well.

If a phone is based on Nucleus, the Nucleus version can be found by analyzing copyright strings in a phone's firmware image.