The evolution of software ecosystems is the result of the popularity and adoption of common architectural development for multiple product development and represents a significant shift in traditional software development style and process methodology. Currently several organizations are in practice with this new process model that embraces business as one of its central factors and have thrived as a result. There can be no doubt that the development of software ecosystems have caused major players in the software industry to rethink their operating practices and engage with third parties, opening their platforms to external entities to attain business objectives. In this paper we examine four of the organizations that are at the forefront of software ecosystem adoption, specifically for mobile devices and explore their business development models. This investigation explores and compares their business process models in terms of how they engage with the external players in order to develop and distribute software and services in this changing marketplace. The study found some commonalities as well as some salient differences in their business processes and presents an assessment of the health of each mobile OS-centric ecosystem. We conclude that this study will help in further aiding understanding of the business process role in this area of ecosystem software.