Android is a open source Linux-based operating system for mobile devices like smartphones and tablet computers developed by the Open Handset Alliance led by Google.Android was purchased by Google in 2005 from Android Inc in a move to gain an edge in the mobile arena.Google is actively developing the platform and is giving it free to hardware manufacturers and phone carriers who want to use Android on their device. Google released Android distribution in 2007 as open-source, under the Apache License, with the formation of the Open Handset Alliance, a consortium of 86 hardware, software, and telecommunication companies aiming to advancing open standards for mobile devices.
Android was designed primarily for smartphones and tablets,though the open source nature of the android allowed it to be used laptops and netbooks, smartbooks,ebook readers, and smart TVs.It also finds its application in wristwatches, headphones, car CD and DVD players, smart glasses, refrigerators, vehicle satnav systems, home automation systems, games consoles, mirrors, cameras, portable media players landlines, and treadmills
The main advantage of adopting Android is that it offers a unified approach to application development. Developers need only to develop for Android, and their applications should be able to run on numerous different devices, as long as the devices are powered using Android. As it is Open source, developers all over the world can write apps in android by downloading the SDK from their official website and publish it in Google play[Android Market].These applications which are avalable in Google Play can be downloaded [mostly fre] directly from there handset.There are both paid and free apps are available in google play. Till now 10 billion apps have downloaded from android market there are more then 4 lac apps available in the Google play.
Android versions
Android 1.0 – 23 September 2008
Android 1.1 – 9 February 2009
1.5 Cupcake – 30 April 2009
1.6 Donut - 15 September 2009
2.0 Eclair – 26 October 2009
2.2. Froyo – 20 May 2010
2.3. Gingerbread – 6 December 2010
3.x Honeycomb – 22 February 2011
4.x Ice Cream Sandwich - 19 October 2011
Current Features and Specifications
Handset
The platform is adaptable to larger, VGA, 2D graphics library, 3D graphics library based on OpenGL ES 2.0 specifications, and traditional smartphone layouts.
Storage
SQLite, a lightweight relational database, is used for data storage purposes.
External storage
Most Android devices include microSD slot and can read microSD cards formatted with FAT32, Ext3fs or Ext4fs file system.
Messaging
SMS and MMS are available forms of messaging, including threaded text messaging and now Android Cloud To Device Messaging (C2DM) is also a part of Android Push Messaging service.
Multiple language support
Android supports multiple languages.
Web browser
The web browser available in Android is based on the open-source WebKit layout engine, coupled with Chrome’s V8 JavaScript engine.
Java support
While most Android applications are written in Java, there is no Java Virtual Machine in the platform and Java byte code is not executed.
Connectivity
Android supports connectivity technologies including GSM/EDGE, IDEN, CDMA, EV-DO, UMTS, Bluetooth, Wi-Fi, LTE, NFC and WiMAX.
Media support
Android supports the following audio/video/still media formats: WebM, H.263, H.264 (in 3GP or MP4 container), MPEG-4 SP, AMR, AMR-WB (in 3GP container), AAC, HE-AAC (in MP4 or 3GP container), MP3, MIDI, Ogg Vorbis, FLAC, WAV, JPEG, PNG, GIF, BMP, WebP.
Streaming media support
RTP/RTSP streaming (3GPP PSS, ISMA), HTML progressive download (HTML5 <video> tag). Adobe Flash Streaming (RTMP) and HTTP Dynamic Streaming are supported by the Flash plugin. Apple HTTP Live Streaming is supported by RealPlayer for Android, and by the operating system in Android 3.0 (Honeycomb).
Additional hardware support
Android can use video/still cameras, touchscreens, GPS, accelerometers, gyroscopes, barometers, magnetometers, dedicated gaming controls, proximity and pressure sensors, thermometers, accelerated 2D bit blits (with hardware orientation, scaling, pixel format conversion) and accelerated 3D graphics.
Multi-touch
Android has native support for multi-touch which was initially made available in handsets such as the HTC Hero. The feature was originally disabled at the kernel level (possibly to avoid infringing Apple’s patents on touch-screen technology at the time). Google has since released an update for the Nexus One and the Motorola Droid which enables multi-touch natively.
Bluetooth
Supports A2DP, AVRCP, sending files (OPP), accessing the phone book (PBAP), voice dialing and sending contacts between phones. Keyboard, mouse and joystick (HID) support is available in Android 3.1+, and in earlier versions through manufacturer customizations and third-party applications.
Video calling
Android does not support native video calling, but some handsets have a customized version of the operating system that supports it, either via the UMTS network (like the Samsung Galaxy S) or over IP. Video calling through Google Talk is available in Android 2.3.4 and later. Gingerbread allows Nexus S to place Internet calls with a SIP account. This allows for enhanced VoIP dialing to other SIP accounts and even phone numbers. Skype 2.1 offers video calling in Android 2.3, including front camera support.
Multitasking
Multitasking of applications is available.
Voice based features
Google search through voice has been available since initial release. Voice actions for calling, texting, navigation, etc. are supported on Android 2.2 onwards.
Tethering
Android supports tethering, which allows a phone to be used as a wireless/wired Wi-Fi hotspot. Before Android 2.2 this was supported by third-party applications or manufacturer customizations.
Screen capture
Android supports capturing a screenshot by pressing the power and volume-down buttons at the same time. Prior to Android 4.0, the only methods of capturing a screenshot were through manufacturer and third-party customizations or otherwise by using a PC connection (DDMS developer’s tool). These alternative methods are still available with the latest Android.
Multi-touch
Android has native support for multi-touch which was initially made available in handsets such as the HTC Hero. The feature was originally disabled at the kernel level (possibly to avoid infringing Apple’s patents on touch-screen technology at the time). Google has since released an update for the Nexus One and the Motorola Droid which enables multi-touch natively.
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