Nice and usefull apps
Android is a software stack for mobile devices that includes an operating system, middleware and key applications. The Android SDK provides the tools and APIs necessary to begin developing applications on the Android platform using the Java programming language. Android is a Linux-based operating system for mobile devices such as smartphones and tablet computers. It is developed by the Open Handset Alliance, led by Google, and other companies.
Google acquired Android Inc. on August 17, 2005, making Android Inc. a wholly owned subsidiary of Google Inc. Key employees of Android Inc., including Andy Rubin, Rich Miner and Chris White, stayed at the company after the acquisition. Not much was known about Android Inc. at the time of the acquisition, but many assumed that Google was planning to enter the mobile phone market with this move.
The difference between the 2.x and 3.x versions of Android is mainly in how they use the screen space provided. Because Android 3.x is designed to run on tablets, its apps have been altered to be able to fit more information on the screen at one time. It also puts all buttons for navigation in the interface, while Android 2.x devices tend to include some physical buttons (usually Home, Back, Menu and Search keys).
The following diagram shows the major components of the Android operating system. Each section is described in more detail below.