What is the Open Handset Alliance Devoted to advancing open standards for mobile devices Develop technologies that will significantly lower the cost of developing and distributing mobile devices and services OHA is complete set of software for mobile devices
Hardware Android is not a single piece of hardware; it's a complete, end-to-end software platform that can be adapted to work on any number of hardware configurations. Everything is there, from the boot loader all the way up to the applications.
Linux Kernel Device drivers Memory management Process management Networking Operating System
C/C++ libraries Interface through Java 2D and 3D graphics SQLite, Browser engine Libraries
Dalvik VM –Dex files –Compact and efficient than class files –Limited memory and battery power Core Libraries –Java 5 Standard edition –Collections, I/O etc… Android Runtime
Android applications are compiled to Dalvik byte code Write app in Java Compiled in Java Transformed to Dalvik byte code Linux OS Loaded into Dalvik VM
Network Connectivity It supports wireless communications using: GSM mobile-phone technology 3G 802.11 Wi-Fi networks Security Android is a multi-process system, in which each application (and parts of the system) runs in its own process. Process permissions are enforced at user and group IDs assigned to processes
Security Android is a multi-process system, in which each application (and parts of the system) runs in its own process. Process permissions are enforced at user and group IDs assigned to processes
API interface Activity manager – manages application life cycle. Application Frame work
Typically correspond to one UI screen But, they can: Be faceless Be in a floating window Return a value Activities Content Providers Enables sharing of data across applications -E.g. address book, photo gallery Provides uniform APIs for: -querying -delete, update and insert.