Well, for them to develop for us its not only simply porting over their app to our platform but also providing us with end-user support...if you go through this thread, you can see how important end-user support is especially for such apps with bring about it various types of users... Opera is a known supporter for open source platforms and yet they have only 2 devs who develop it for us in their free time as an experiment if you read thier disclaimers... So what hope do we have from Viber, Whatsapp or Skype supporting us further? After all Skype is integrated into our system and is now a component of M$ which has never supported F/OSS... Take for example a famous iOS game called Temple Run, its being selling like crazy but recently they ported it over to Android and hired 2devs to do just this specifically but still faced many issues leading to various updates that have led some newer models (Galaxy Nexus with JB) not able to run it while some older ones (SGS) running it... Development is not a simple task so if you are not going to get volume why bother in the first place? Yes, I agree they could do more but if you are in their shoes and you can earn by improving the dev teams of the existing platforms or risk by hiring new devs for a supposedly "dead" platform what would you do?