Google's Android Market has passed 10 billion app downloads, a major milestone for the popular mobile operating system. "One billion is a pretty big number by any measurement. However, when it's describing the speed at which something is growing, it's simply amazing," said Eric Chu, director of the Android Developer Ecosystem, in a company blog post. "This past weekend, thanks to Android users around the world, Android Market exceeded 10 billion app downloads -- with a growth rate of 1 billion app downloads per month."

To celebrate this milestone, Google partnered with some of the Android developers who contributed to this milestone to make a bunch of Android apps available at low prices. Starting today for the next 10 days, Google will have a new set of apps available each day for only 10 cents each. Today, Google is starting with Asphalt 6 HD, Color & Draw for Kids, Endomondo Sports Tracker Pro, Fieldrunners HD, Great Little War Game, Minecraft, Paper Camera, Sketchbook Mobile, Soundhound Infinity and SwiftKey X.

More than 200 million Android smartphones and tablets have been sold and about 550,000 new Android activations take place each day, Google has said.

Apple passed 15 billion downloads from its App Store in July, noting that there are more than 200 million iPad, iPhone and iPod Touch users worldwide.