Android Version History

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 under ongoing development by Google and the Open Handset Alliance (OHA), and has seen a number of updates to its base operating system since its initial release.

The most recent major Android update is Android 5.0 "Lollipop", which was released on November 3, 2014. Since April 2009, Android versions have been developed under a confectionery-themed code name and released in alphabetical order, beginning with Android 1.5 "Cupcake"; the earlier versions 1.0 and 1.1 were not released under specific code names:

• Alpha (1.0)
• Beta (1.1)
• 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 (4.1–4.3.1)
• KitKat (4.4–4.4.4, 4.4W–4.4W.2)
• Lollipop (5.0–5.1)

On September 3, 2013, Google announced that one billion activated Android devices were in use worldwide.[2] In January 2015, Android devices accounted for approximately 62% of the US smartphone and tablet market, 82.7% of the Chinese market, and 73.3% of the European market.

source:Wikipedia