Introduction to Android
Android is a set of software for mobile devices as we can take the following examples - computers, tablets, notebooks, smartphones, smart watches, setup boxes, electronic book reader, etc.
The Android commonly used to refer to the operating system, also we can say that Android is a complete software stack that contains an operating system based on Linux but specifically designed to run on mobile devices.
It also includes a complete application framework so that we can create or deploy our own custom apps.
History of Android
Initially, ANDY RUBIN founded Android incorporation in polo alto, California, United States in October 2003. On August 17, 2005, Google acquired Android incorporation, since then it is in the subsidiary of GOOGLE Incorporation.
Versions of Android
The versions of Android are interesting to know. The names of android versions ranges from A to M currently and having names on delicious desert described in the following table:
| Version Name | Code name | API Level | Released |
| ANDROID 1.0 | - | - | September 2008 |
| ANDROID 1.1 | - | - | February 2009 |
| ANDROID 1.5 | Cupcake | 3 | April 2009 |
| ANDROID 1.6 | Donut | 4 | September 2009 |
| ANDROID 2.1 | Eclair | 7 | October 2009 |
| ANDROID 2.2 | Froyo | 8 | May 2009 |
| ANDROID 2.3 | Gingerbread | 9 and 10 | December 2010 |
| ANDROID 3.1,3.3 | Honeycomb | 12 and 13 | February 2011 |
| ANDROID 4.0 | Ice Cream Sandwitch | 15 | October 2011 |
| ANDROID 4.1,4.2,4.3 | Jelly Beans | 16 , 17 and 18 | 2011 – 13 |
| ANDROID 4.4 | Kitkat | 19 | October 2013 |
| ANDROID 5.0 | Lollipop | 21 | - |
Basic Building Blocks of Android
In Android application development we have these basic building blocks for coding of android application.
- Activity
- Intent
- Content Provider
- Service
- Broadcast Receiver
- Service
Categories of android applications
There are many kinds of applications available in online market, the categories are defined here:
- Entertainment
- Tools
- Communication
- Music and Audio
- Social apps
- Media and Video
- Travel and Local
- Locating etc
Activity Life Cycle
![Activity Life Cycle]()