Tumblr Chief Executive David Karp has focused on building the company's user basefor its minimalist blogging platform while leaving for later the question of earning money.
As Android is free, and the current number 2, iOS, is not even available for licensing, any of the Android makers who launches product on other platforms migrates to a tiny system which has under 4% sales, and for any new platform, even less in installed base.
He likens the situation to the early days of iOS, when smart developers recognized that it was a platform worth building for despite the then-small user base.