The low barrier to entry for development is going to be important too. The development tools are free and run on low-end hardware and you don't have to pay a fee to distribute apps outside the app store.
Make no mistake, this is why Apple and Microsoft are afraid of Android and it makes their selfish bullying that much more reprehensible. Apple is never going to make an $80 phone.
And Google advocating for more android developers here in kenya helps. In fact they have a dev conference next month in Nairobi and Android is one of the topic list(plus GAE,GWT, chrome).
Make no mistake, this is why Apple and Microsoft are afraid of Android and it makes their selfish bullying that much more reprehensible. Apple is never going to make an $80 phone.