This will sound pretty dumb, but with all the amazing cross platform games written in Unity - which I thought was Mono or some form of cross platform library with .NET as one of the primary languages, I always wondered why there was not a more 'business app version' of this. After using Xamarin, Appcelerator, and dozens of other 'cross platform tools', with to be let down from ALL of them in the end and/or support dropped.... Having to support multiple platforms, esp. IOS vs. Android still seems to be stuck in the stone ages, esp. for small dev teams that can't allocate massive resources to multi-platform...