Cortex A processor is designed for application systems. Application processors are the powerhouse chips, running complete operating systems, high performance multimeter codes, and demanding applications. They have MMV.

They are targeted at mobile devices that require advanced calculation or graphics. Smartphones, tablets, digital TVs are powered by cortex A and even laptops are developed running on multicore cortex A cores.

Cortex R profile is for real-time applications for critical systems where reliability is crucial and speed is decisive. Real-time systems are designed to handle fast changing data, and to be sufficiently responsive to handle the data throughput without slowing down.

These are found in hard drives, network equipment and embedded into critical systems, such as car brake assistance.

Cortex M is designed for microcontroller applications. These applications typically require little processing power, lot of input and output lines, small form factor, deterministic interrupt response and low power consumption.

They are used in Bluetooth devices, touchscreen controller. Cortex M chips are designed for rapid development, since entire application, including vector tables can be written in C.