iUI is a mobile web framework that has been around for a long time (since 2007) compared to many other mobile resources.
It was mentioned in a previous WRD article (iPhone Application And Website Development: All Tools And Tutorials You Need) and evolved much since then.
User interfaces to be created are iPhone-like yet compatible with most smartphones and tablets and has support for menus, forms, lists, image galleries and more.
Also, there are built-in extensions for caching, getting system information, HTML5 videos or theme switching.
iUI is well-documented and has tutorials to get you started easily.
Compatibility: All Major Smartphones & Tablets