What is Android Operating System ?

Android is an Open Source Linux Based Operating System For Mobile Devices Such As SmartPhones , Android Tablets. Android was developed by Open Handset Alliance,led by Google and Some Other Companies.

Android is owned by Google, meaning you will find some of their other services already on your device, such as Gmail, YouTube and Google Maps while the manufacturer usually adds their own apps too. For example, Samsung’s new mobile payment app Samsung Pay will be found on the Galaxy S6 edge+, while the Hudl comes with the Tesco Groceries app to do your shopping online.

The Google Play store is the main place to go for downloading more than 700,000 other apps, whether you’re into social media on Facebook, catching up with television on the BBC iPlayer or playing Candy Crush - a simple search will find a whole variety of apps and new ones are being added continuously. There are also dedicated sections to download paid-for books, music, movies and television shows too.

Each year Google updates Android for free with some new features and upgrades behind-the-scenes, working its way through the alphabet using the name of a sweet to differentiate each version. The most recent version of Android is called Lollipop, but Google is already planning to roll out its next offering, Android Marshmallow later this year.

Features of Android

Android is a powerful operating system competing with Apple 4GS and supports great features. Few of them are listed below:

Feature	Description
Beautiful UI	Android OS basic screen provides a beautiful and intuitive user interface.
Connectivity	GSM/EDGE, IDEN, CDMA, EV-DO, UMTS, Bluetooth, Wi-Fi, LTE, NFC and WiMAX.
Storage	SQLite, a lightweight relational database, is used for data storage purposes.
Media support	H.263, H.264, MPEG-4 SP, AMR, AMR-WB, AAC, HE-AAC, AAC 5.1, MP3, MIDI, Ogg Vorbis, WAV, JPEG, PNG, GIF, and BMP
Messaging	SMS and MMS
Web browser	Based on the open-source WebKit layout engine, coupled with Chrome's V8 JavaScript engine supporting HTML5 and CSS3.
Multi-touch	Android has native support for multi-touch which was initially made available in handsets such as the HTC Hero.
Multi-tasking	User can jump from one task to another and same time various application can run simultaneously.
Resizable widgets	Widgets are resizable, so users can expand them to show more content or shrink them to save space
Multi-Language	Supports single direction and bi-directional text.
GCM	Google Cloud Messaging (GCM) is a service that lets developers send short message data to their users on Android devices, without needing a proprietary sync solution.
Wi-Fi Direct	A technology that lets apps discover and pair directly, over a high-bandwidth peer-to-peer connection.
Android Beam	A popular NFC-based technology that lets users instantly share, just by touching two NFC-enabled phones together.

Android Applications

Android applications are usually developed in the Java language using the Android Software Development Kit.

Once developed, Android applications can be packaged easily and sold out either through a store such as Google Play,SlideME,Opera Mobile Store,Mobango,F-droid and the Amazon Appstore.

Android powers hundreds of millions of mobile devices in more than 190 countries around the world. It's the largest installed base of any mobile platform and growing fast. Every day more than 1 million new Android devices are activated worldwide.

This tutorial has been written with an aim to teach you how to develop and package Android application. We will start from environment setup for Android application programming and then drill down to look into various aspects of Android applications.

Android versions

Since its development there have been many different versions of Android, which is why if you have multiple android devices in your house (e.g. a phone and a tablet) there be noticeable differences. Below is a listing of each of the different major Android versions.

Android version 1.0 released September 23, 2008
Android version 1.5 (Cupcake) released April 27, 2009
Android version 1.6 (Donut) released September 15, 2009
Android version 2.0 released (Eclair) October 29, 2009
Android version 2.1 released January 12, 2010
Android version 2.2 (Froyo) released May 20, 2010
Android version 2.3 (Gingerbread) released December 6, 2010
Android version 3.0 (Honeycomb) released February 22, 2011
Android version 3.1 released May 10, 2011
Android version 3.2 released July 15, 2011
Android version 4.0 (Ice Cream Sandwich) released October 8, 2011
Android version 4.1 (Jelly Bean) released July 9, 2012
Android version 4.2 released November 13, 2012
Android version 4.3 released July 24, 2013
Android version 4.4 (KitKat) released October 31, 2013
Android version 5.0 (Lollipop) released November 3, 2014
Android version 6.0 (Marshmallow) released May 28, 2015