Happy Birthday Android

When Android was launched as an operating system in 2007, many experts claimed that Google had left it too late to make an impact on the smartphone market. Now, five years after its official launch, Google's Android has become the world's most popular mobile device operating system.

So as Android celebrates its fifth birthday this week, here are some of the numerical milestones it has passed on its way to world domination.

Though Android wasn't revealed as an operating system until November 5, 2007, 2005 is the year in which the company behind the open source code, Android Inc., was bought by Google. Android Inc. had been formed in 2003 with the mission of developing smarter mobile devices that are more aware of their owners' location and preferences. Google funded much of this early development and, after the acquisition, the company's founders remained.

The number of hardware, software and telecommunications companies that currently make up the Open Handset Alliance, the group dedicated to advancing open standards for mobile devices. As well as Google, members include HTC, Samsung and network carriers such as T-Mobile.

October 22, 2008 was the date of the first Android smartphone, the HTC Dream (sold in the US as the T-Mobile G1), released a year after Google launched the Android operating system and after Apple had rocked the smartphone world with the first incarnation of its iPhone.

The year Google launched its first Nexus device, the Nexus One smartphone, and, like all Nexus devices that have followed, it was designed as a flagship product to showcase Android and show developers what it is capable of first, and delight consumers second. 2010 is also the year when Android overtook Symbian to become the world's most popular smartphone operating system.

Number of apps and games available on the Google Play Store as of September 2012

25 billion
Number of app downloads between 2008 and 2012. Android hit this milestone on September 26, 2012. At the same time, the number of Android device activations hit 500 million and Google claimed that the number of Android users was growing by 1.3 million a day.

The percentage of Android devices that are still running Gingerbread, version 2.3 of the Android operating system. The latest version of the software, Jellybean (4.1), has been available since July yet is still only available on 2.7 percent of devices. This highlights one of the problems of an open source platform used by many different device makers in many different territories. It's nowhere near as easy to upgrade the software on millions of totally different devices with different chips and drivers as it is when, like Apple, no one else makes your hardware or shares your software.

181 million
The number of Android phones shipped worldwide in the third quarter of 2012 alone, giving it a 75 percent share of the market compared with Apple's 14.9 percent. Incidentally, 181 million sales in one quarter is greater than the total number of smartphones sold worldwide in 2007, the year Android was launched.