Android is an operating system developed by Android, Inc. later purchased by Google. The operating system was developed from the Linux kernel and uses the Java language for developing applications that run on top of this system.
This operating system is open-source, meaning free to use and modify.
Android SDK contains a set of tools to build and develop Android-based application which includes a debugger, libraries, emulator, documentation, sample code, and tutorials.
Features available on Android is:
* Framework applications: it allows the use and removal of components available.
* Dalvik virtual machine: a virtual machine optimized for mobile devices.
* Graphs: the graph in 2D and 3D graphics based on OpenGL library.
* SQLite: for data storage.
* Supports media: audio, video, and various image formats (MPEG4, H.264, MP3,
AAC, AMR, JPG, PNG, GIF)
* GSM, Bluetooth, EDGE, 3G, and WiFi (hardware dependent)
* Camera, Global Positioning System (GPS), compass, and accelerometer (hardware
dependent)

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