But almost all developers with support both anyway.
In its second annual developer survey, Ovum has found that the two major platforms remain ahead, but that that coders are also embracing new OSs and web-based standards such as HTML5.
They're fast abandoning fading alternatives such as Windows Mobile, Symbian and WebOS too.
Yet, despite the increasing use of cross-platform programming approaches, most developers are still using vendor-specific distribution channels (such as Android Market) to deploy apps, as this is seen as the best way to reach the largest possible audience for their applications.
Adam Leach, devices & platforms practice leader at Ovum and author of the research, said: “A smartphone platform’s success is dictated not only by the pull of consumers and the push of handset vendors and mobile operators but also by a healthy economy of applications delivered by third-party developers.
"Therefore, it is important for all players in the smartphone ecosystem to understand the choices developers are making today and the downstream impact of those choices.