As we know android is Linux Kernel based operating system, it is also stack of software components that means it has more than one software including Linux Kernel. So here is detailed information about its architecture .In below image there are four layers and five blocks.
Linux Kernel (Device driver layer) is bottom layer components of this stack. The purpose of drivers is to access hardwares like Camera, Display Bluethooth, USB etc.t
This is the top of Linux Kernel layer. There are set of libraries written in C and C++. SQLite , OpenGL , SSL are few of them.
Android runtime introduced in 5.0 API. ART is replacement of Dalvik Virtual Machine . In this block each application creates separate virtual environment to run.
Application developer use this framework to create an android application. This layer contains Java classes like Activity manager , Window Manager , Content Providers , View System and many more.
This is the top layer of android Architecture. These applications are the system level applications for instance, Call, Messaging, Browser application.