Introduction

           

 Android is an operating system based on LINUX Kernel and Designed primarily for Touch Screen Mobile Devices such as Smartphone and tablets Computer.Initially developed by Android, Inc., which Google backed financially and later bought in 2005, Android was unveiled in 2007 along with the founding of the Open Handset Alliance: a consortium of  hardware, software, and telecommunication companies devoted to advancing open Standers for mobile devices The first publicly available smartphone running Android, the HTC Dreams, was released on October 22, 2008.

                 The user interface of Android is based on direct manipulation, using touch inputs that loosely correspond to real-world actions, like swiping, tapping, pinching and reverse pinching to manipulate on-screen objects. Internal hardware such as accelerometers, gyroscopes and proximity sensors are used by some applications to respond to additional user actions, for example adjusting the screen from portrait to landscape depending on how the device is oriented. Android allows users to customize their home screens with shortcuts to applications and widgets, which allow users to display live content, such as emails and weather information, directly on the home screen.Applications can further send notifications to the user to inform them of relevant information, such as new emails and text messages.

                         As of July 2013, Android has the largest number of applications ("apps"), available for download in Google Play" store which has had over 1 million apps published, and over 50 billion downloads.A developer survey conducted in April–May 2013 found that Android is the most used platform among developers: it is used by 71% of the mobile developers population. 

                      As of May 2012, Android became the most popular mobil OS, having the largest installed base, and is a market leader in most countries including the United States; there it has had the highest installed base of mobile phones for years. In the third quarter of 2013, Android's share of the global smartphone shipment market—led by Samsung products—was 81.3%, the highest ever. The operating system's success has made it a target for patent litigation as part of the so-called "smartphone wars" between technology companies. As of September 2013, one billion Android devices have been activated.

History

Android, Inc. was founded in Palo Alto, California in October 2003 by Andy Rubin (co-founder of Danger), Rich Miner (co-founder of Wildfire Communications, Inc.). Nick Sears (once VP at T-Mobile), and Chris White (headed design and interface development at WebTV) to develop, in Rubin's words "smarter mobile devices that are more aware of its owner's location and preferences". The early intentions of the company were to develop an advanced operating system for digital cameras, when it was realized that the market for the devices was not large enough, and diverted their efforts to producing a smartphone operating system to rival those of Symbian and Windows Mobile.

                        Google acquired Android Inc. on August 17, 2005; key employees of Android Inc., including Rubin, Miner and White, stayed at the company after the acquisition Not much was known about Android Inc. at the time, but many assumed that Google was planning to enter the mobile phone market with this move. At Google, the team led by Rubin developed a mobile device platform powered by the Linux kernel. Google marketed the platform to handset makers and carriers on the promise of providing a flexible, upgradable system. Google had lined up a series of hardware component and software partners and signaled to carriers that it was open to various degrees of cooperation on their part.

                        On November 5, 2007, the Open Handset Alliance, a consortium of technology companies including Google, device manufacturers such as HTC,Sony and Samsung, wireless carriers such as Sprint Nextel and T-Mobile, and chipset makers such as Qualcomm and Texas Instruments, unveiled itself, with a goal to develop open standards for mobile devices. That day, Android was unveiled as its first product, a mobile device platform built on the Linux kernel version 2.6. The first commercially available smartphone running Android was the HTC Dream, released on October 22, 2008.

                                In 2010, Google launched its Nexus series of devices – a line of smartphones and tablets running the Android operating system, and built by a manufacturing partner. HTC collaborated with Google to release the first Nexus smartphone, the Nexus One. The series has since been updated with newer devices, such as the Nexus 5 phone and Nexus 7 tablet, made by LG and Asus respectively. Google releases the Nexus phones and tablets to act as their flagship Android devices, demonstrating Android's latest software and hardware features.

Interface

Android's user interface is based on direct manipulation,^] using touch inputs that loosely correspond to real-world actions, like swiping, tapping, pinching and reverse pinching to manipulate on-screen objects.  Internal hardware such as accelerometers, gyroscopes and proximity sensor are used by some applications to respond to additional user actions, for example adjusting the screen from portrait to landscape depending on how the device is oriented, or allowing the user to steer a vehicle in a racing game by rotating the device, simulating control of a steering wheel

                         A home screen may be made up of several pages that the user can swipe back and forth between, though Android's home screen interface is heavily customizable, allowing the user to adjust the look and feel of the device to their tastes. Third-party apps available on Google Play and other app stores can extensively re-theme the home screen, and even mimic the look of other operating systems, such as Windows Phone.

                        Present along the top of the screen is a status bar, showing information about the device and its connectivity. This status bar can be "pulled" down to reveal a notification screen where apps display important information or updates, such as a newly received email or SMS text, in a way that does not immediately interrupt or inconvenience the user.

Latest Version

Android 4.0-4.0.2 Ice Cream Sandwich(API Level 14)

The SDK for Android 4.0.1 (Ice Cream Sandwich), based on Linux kernel 3.0.1, was publicly released on 19 October 2011. Google's Gabe Cohen stated that Android 4.0 was "theoretically compatible" with any Android 2.3.x device in production at that time. The source code for Android 4.0 became available on 14 November 2011. Ice Cream Sandwich was the last version to officially support Adobe Systems' Flash player. The update introduced numerous new features:

Android 4.1 Jeally Bean (API Level 16)

Google announced Android 4.1 (Jelly Bean) at the Google I/O conference on 27 June 2012. Based on Linux kernel 3.0.31, Jelly Bean was an incremental update with the primary aim of improving the functionality and performance of the user interface. The performance improvement involved "Project Butter", which uses touch anticipation, triple buffering, extended vsync timing and a fixed frame rate of 60 fps to create a fluid and "buttery-smooth" UI. Android 4.1 Jelly Bean was released to the Android Open Source Project on 9 July 2012, and the Nexus 7 tablet, the first device to run Jelly Bean, was released on 13 July 2012.

Android 4.2 Jeally Bean (API Level 17)

Google was expected to announce Jelly Bean 4.2 at an event in New York City on 29 October 2012, but the event was cancelled due to Hurricane Sandy. Instead of rescheduling the live event, Google announced the new version with a press release, under the slogan "A new flavor of Jelly Bean". Jelly Bean 4.2 was based on Linux kernel 3.4.0, and debuted on Google's Nexus 4 and Nexus 10, which were released on 13 November 2012.

Android 4.3 Jelly Bean (API Level 18)

Google released Jelly Bean 4.3 under the slogan "An even sweeter Jelly Bean" on 24 July 2013 during an event in San Francisco called "Breakfast with Sundar Pichai". Most Nexus devices received the update within a week, although the 2nd generation Nexus 7 tablet was the first device to officially ship with it. A minor bug fixing update was released on 22 August 2013.

Android 4.4 Jelly Bean (API Level 19)

Google announced Android 4.4 KitKat, internally known as Project Svelte, on 3 September 2013. The release had long been expected by technology bloggers to be numbered 5.0 and called "Key Lime Pie". KitKat debuted on Google's Nexus 5, and has been optimized to run on a greater range of devices than earlier Android versions, having 512 MB of RAM as a recommended minimum.