Chipset, CPU and SoC
Chipset : Chipset basically is the motherboard in a phone which accepts all the components to sit upon it, and connect with each other. It is made of ICs and provides all the inter communication channels (buses) to connect for eg Camera, bluetooth, wifi, touch screen with CPU/Flash Storage/RAM.
CPU : CPU is the Central Processing Unit which is responsible for carrying out the instructions of a computer program by performing the basic arithmetical, logical, and input/output operations of the system.
Almost all CPUs in mobile’s are based on specifications by ARM (Cortex A7/A9/A15 etc.).
SoC (System on Chip) : In a mobile phone, combination of Chipset and CPU is called a SoC (System on Chip) which integrates all the components on a single chip. Unlike in computers, CPU is soldered on the Chipset inside a mobile device which tends to improve the performance, and saves lot of space.
Popular SoCs are Snapdragon by Qualcomm, Tegra by nVidia, Intel Atom (SoC).