Android's goal was to be a common baseline that enables innovation in the mobile space. Convincing other companies to use Android wasn't easy and that's one of the biggest Google accomplishments. Not many people believed in Android's success three years ago and its adoption rate is still surprising.
Convincing companies to update their Android-based firmware faster is much easier. If users only buy Android phones that have the latest version of the operating system and constantly request phone manufacturers and carriers to update the software, then they'll work harder to improve their products.
Google has recently released some information about the current distribution of the Android versions and the good news is that 87.4% of the Android phones use Android 2.x, up from about 55% in July. 51.8% of the phones use Froyo, a version released 7 months ago. In only one month (August 2010), Froyo's share grew from 5.5% to more than 28%, after Motorola and HTC updated phones like Droid, Droid Incredible, Evo 4G, and Desire.
ZDNet says that "almost 13% of Android users are still running versions of the mobile OS that are several generations old and these users will never see Android 2.1", but this percentage is constantly decreasing. Even if they're using Android 1.6, that's still a much better operating system than the one from a feature phone and it still lets them use many apps from the Android Market. A slower update rate is a small price to pay for creating an ecosystem of heterogeneous devices that run the same operating system which is not perfect, but it's "good enough".
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