Re: Thinking about driving from South Africa to Tanzania. Jan 29, 2013, 5:40 AM. good to hear. right now we are in SA and are thinking to make our way up to Tanzania for Safari in Mid-March (departing SA beginning of February). That would make about 6 weeks of driving.
To summarize, C# programming language can be used to build Windows app using the .NET platform, and can also be used to build Linux app using the Mono platform. It cannot be used to make an Android app, but with persistence, in theory, you can wrap it around the Android NDK framework.
To install C#, for the moment anyway, you don't need to purchase a thing. You just need to get your hands on the Microsoft .Net Framework. C# is a language that comes with the Microsoft .Net (pronounced DOT-NET) Framework. The .Net Framework is an environment that permits .Net programs to run. C# is just one of many programming languages supported by the .Net framework (it even includes COBOL).