The one thing that Jquerymobile does not support is the native device api. I've done development with both, but atleast with android, creating an interface for javascript function calls was easy. The Jquery mobile ui's work quite smoothly on many different android phones, even low end.
Currently I'm using just jquery mobile, the difference being here that its just for the ui, not an API for device functionality. Also, im doing the jquery mobile development through titanium,
http://www.appcelerator.com/platform
