This video from Google lets you visualize the evolution of Android activations from October 2008 to January 2011. HTC Dream/G1, the first Android device, was launched in the US and the UK in October 2008 and it became available in other countries in 2009, but it wasn't until the launch of Motorola Droid in November 2009 that Android became popular.
Android Central says that this is "a staggering reminder of just how far Android has come in a relatively short amount of time". Eric Schmidt has recently mentioned that the average number of daily Android activations is now 350,000, up from 300,000 in December, 200,000 in August and 60,000 in April 2010.
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