Martin Fowler’s slides on cross-mobile platform development here: http://martinfowler.com/articles/multiMobile/

C++
http://blog.burhum.com/post/36166554007/cross-platform-ios-android-mobile-app-development

UI options:
http://www.dodgycoder.net/2012/01/modern-cross-platform-development.html

c++ on the web:

Mixed one:
http://www.geekwire.com/2012/apps-cross-platform/