An Introduction: The version history of the Android mobile operating system began with the release of the Android beta in November 2007. The first commercial version, Android 1.0, was released in September 2008.Android is developed by Google and the Open Handset Alliance. There have been a number of updates to the initial Android Version. Android versions have been developed under a codename and released according to alphabetical order: Cupcake (1.5), Donut (1.6), Eclair (2.0–2.1), Froyo (2.2–2.2.3), Gingerbread (2.3–2.3.7), Honeycomb (3.0–3.2.6), Ice Cream Sandwich (4.0–4.0.4), Jelly Bean (4.1–4.3), and KitKat (4.4) followed by Lollipop (5.0). The most recent major Android update was Lollipop 5.0, which was released on commercially and Google announced Kit Kat's successor as Android 4.4. What's so different in Android? The good news is for both the consumers and developers. While consumers could enjoy a low-cost Smart phones running Android, developers were given an unrestricted customization rights
. With a new version been released in the market frequently (almost every six months) it is important to understand the users mind set towards up-gradation. Android has eight different versions commercially launched .Official Announcement has been made to launch the ninth version soon.
. Android Mobile Operating Systems has been evolving under the influence of three main factors Developers, Application Developers and End users.
 Uses of Android are now far exceeding its original expectations. It has been implemented for different uses such as house hold applications, wristwatches, DVD players’, car stereos etc. Although Android technology is increasingly being used on a range of devices, the most common hardware to use this platform is mobile phones. A large community of developers frequently write applications (apps), including games, social networking, and business modules, for Android smart phones. There are a wide range of free Android apps, including games, and paid apps are even more common. Android technology has given software developers the opportunity to develop, sell and distribute applications to a wide group of consumers.
 With a new version been released frequently (almost every six months) it is important to understand the users mind set towards up-gradation.
 Android by 2012, A study on present and future of Google's Android By Dotcom Infoway
 Jindal Gaurav , “ A Comparative Study of Mobile Phone’s Operating Systems” International Journal of Computer Applications & Information Technology Vol. I, Issue III, November 2012 (ISSN: 2278-7720)  Sony.com (January 2012), Nikkon.com (March 2011)