Microsoft Azure RTOS is comprised of the ThreadX RTOS and a suite of middleware. NXP formerly partnered with Microsoft to deliver Azure RTOS on some devices in its general purpose microcontroller portfolio, delivered as part of MCUXpresso SDK. Microsoft has discontinued Azure RTOS, and so NXP is no longer offering this software as part releases after MCUXpresso SDK 2.15, and is unable to guarantee technical support. A version of the software is available under the Eclipse ThreadX project but this is not directly supported by NXP.
NXP continues to fully support FreeRTOS and Zephyr, and several of our Partners offer ports of their RTOSes for our MCU portfolio.