Last two weeks I've estimating Tizen, Ubuntu or Sailfish worth port an app. Like sample apps, build scripts debugging, etc. Although Tizen has large corp support, Ubuntu and Sailfish look more developer friendly. CMake, QT , C++.
C# look like a dead end, though much better than first WinPhone with "SilverLight." If you have written c/ or c++ engine, you need just a good bridge to OS UI language. Well, also platform + tools that work well on each Unix/Linux.
Just to mention I used to like MS technologies.
Least problems I had with ASP 2 / AJAX web app which works for nine years without significant problems.
