I am .NET developer and currently working with WPF and ASP.NET MVC 4. The next project I should start will be a web application with good chance to later create clients for desktop/mobile/tablets. In other words, this application could be used from the web browser but also from native applications on Android, iOS, WinPhone8 and Windows Desktop (WPF). I have very limited experience with iOS development and none with Android dev.
One of the features I plan to have in this product is ability for users to select a language on which they want to use GUI, be it in web browser or any other client. Thus I need to create localization solution that would work with all platforms I plan to support. Since I am starting this project with first creating the web app in ASP.NET MVC I am not interested in using Microsoft's default support for localization via resources files (.resx) since that wouldn't be portable.
What are different options out there for creating multi-language support in apps deployed for various platforms? The first idea is to use XML files but I am also interested in exploring other possible solutions that might already exist out there. Any ideas on how to approach this problem are welcome.