I've been musing the same thing for a little while now. I think Zepto, Backbone, RequireJS and HTML5 Mobile Boilerplate makes a solid foundation for a mobile ap

I've been musing the same thing for a little while now. I think Zepto, Backbone, RequireJS and HTML5 Mobile Boilerplate makes a solid foundation for a mobile app framework, much more lightweight than jQuery Mobile, which is IMO unusable for anything but the simplest of apps. All that is missing is a CSS library to take care of the UI elements and perhaps transitions too. One idea I had was to take the CSS from Sencha /KendoUI / jQTouch and combine with the components above to create a 'Backbone Mobile' framework. I just haven't had the time yet to figure out if this would work.