If you're a developer trying to decide which OS to develop your software on, and market share is a significant factor in your decision, you're going to choose s

If you're a developer trying to decide which OS to develop your software on, and market share is a significant factor in your decision, you're going to choose something cross-platform. That's most likely web, but even if you choose one of the toolkits your choice is going to impact all of the OS producers equally: their marketshare will not be impacted at all by you, unless they actively inhibit cross-platform development on their OS. MS used to do that but not anymore; Apple tries to keep the wall around their garden but they don't block cross-platform completely.